Merrifield 1846
Mary Philadelphia Merrifield, The Art of Fresco Painting, as Practised by the Old Italian and Spanish Masters, with a Preliminary Inquiry into the Nature of the Colours Used in Fresco Painting, with Observations and Notes, London [Charles Gilpin] 1846.
pp. xi–lvi
AN INQUIRY
INTO THE
NATURE OF THE COLOURS
USED IN
FRESCO PAINTING,
BY THE
ITALIAN AND SPANISH MASTERS.
PRELIMINARY OBSERVATIONS.
THE selection of proper coloursa for painting in fresco is among the most important parts of the art. All the best authorities on this subject are unanimous in the opinion, that natural colours only, are proper to be used in fresco painting. Armenino observes, “artificial colours never do well in fresco, nor can any art make them last long without changing, and particularly in the open air; the wall will not take any other than the natural colours which are found in the ground, and which consist of earths of different colours; and you may leave to foolish painters those secrets of theirs which no one envies them, of using vermilion and fine lake, because, although they make grounds for these colours with various tints of white, it is nevertheless well known, that in the long run their pictures become ugly daubs.” Vasari uses nearly the same terms. Pacheco observes, “the colours must be natural colours,” and Palomino says, “they must be all mineral,” by which he means natural and not artificial colours. These and numerous other extracts to the same effect will be found in the subsequent part of this work.
a The authors quoted, almost uniformly use the term “colour,” and therefore both that and the term “pigment” have been used throughout the work as if convertable terms: otherwise, “pigment” would in most cases have been preferred.
The natural colours are neither numerous nor brilliant, but the frescoes of Raphael, Michael Angelo, and others, irresistibly prove, that the colours used by them, were amply sufficient for all the purposes of fresco painting. Some of these colours have for a long time fallen into disuse, and the knowledge of their value, application, and use, is in a great measure lost. Artificial colours and pigments have been improperly substituted, and failed of their object. The consequence has been, that the highest branch of the art of painting, and from which the greatest masters have derived most of their celebrity, has declined and fallen into disuse. The object of the following treatise is, to restore this knowledge, and with this view I have endeavoured, by a diligent examination and perusal of old authors, who have treated on these subjects, to investigate and ascertain the colours formerly employed in painting in fresco. The subject has extended to greater length than I had anticipated, for my object being to re-discover the old and valued colours used at the period when fresco painting was in its greatest perfection, it was necessary to adduce satisfactory evidence as to what colours or pigments were actually used by the great masters of the Italian and Spanish schools. The importance of employing proper pigments, on which the beauty and durability of the painting so much depends, will, I trust, be considered a sufficient reason for having extended my observations and enquiries to a length, which, otherwise, might have been considered unnecessary.
The following passage in the truly valuable Report of the Commissioners on the Fine Arts, namely, that “the problems yet to be solved are, the speedier preparation of a lime, adapted for fresco painting, and the preparation of durable colours of the more florid kind, such as lake and crimson,” (III. Rep. 53.) prompted me to the following investigation, and induced me to consider the subject, with a view to ascertain the nature of the pigments used in the Italian and Spanish schools, to produce these florid colours. I shall first endeavour to ascertain the colours formerly used, to produce the lake and crimson colours in the old fresco paintings.
RED COLOURS. – AMATITO.
DIFFERENT NAMES GIVEN TO AMATITO BY AUTHORS ON PAINTING. – It appears quite clear, that the old masters used a natural colour, which, when opposed to the other colours, appeared like lake, and that this colour is mentioned in terms of praise by many writers on art, who however call it by different names. It also appears that this colour was much used by the school of Giotto, but had almost entirely ceased to be used in Italy previous to 1584, and in France long before the time of De Piles, who was born in 1635 and died in 1709; but it was preserved in Spain at least until the publication of Palomino’s work on painting in 1715–24.
The earliest Italian writer who mentions this colour is Cennino Cennini. In his Treatise on Painting, ch. 42, he says, “there is a red colour called amatito. This is a natural colour, and is prepared from a very hard and firm stone. It is so hard and firm, that tools are made of it to burnish gold on pictures. These become of a dark colour, and are as perfect and good as a diamond. The pure stone is of a purple or morella colour, and has striæ (or fibres) like Cinnabar. Break this stone first in a bronze mortar, because if you were to break it on a porphyry slab, you might split it. And when you have broken it, put what quantity of it you wish to grind on the stone, and grind it with clear water; and the more you grind it the better, and more perfect will be the colour. This colour is good for painting on walls in fresco, and it makes a colour such as cardinals wear, or a purple or lake colour. It cannot be used in any other way or distemper.” And in chapter 136, he says, “choose a piece of lapis amatista, firm and without veins, with its striæ or fibres running longitudinally. Grind it on a grindstone, and make it very smooth and polished, of about the width of two fingers, if you can. Then take some of the dust of emeralds, and rub the stone, until no inequalities remain. Round off all the corners and put it into a handle of wood, with a ferule of brass or copper, and let the handle be round and polished, so that the palm of the hand may rest well upon it. Then give it a lustre in the following manner. Put some charcoal powder on a smooth porphyry slab, and rub the stone on it exactly as if you were burnishing with it, and your stone will become firm, dark, and shining, as a diamond. You must be very careful not to break it or to let it touch iron; and when you would burnish gold or silver with it, put it first into your bosom, to get rid of any dampness, which would soil the gold.”
The next author who mentions the pigment is Borghini (Riposo 168–169.) His words are, “Another red colour is made of Lapis Amatito, (by some called mineral Cinnabar); it is a very hard natural stone, which the sword cutlers, and those who gild leather, use to burnish gold; and because it is very difficult to grind, it is thought a good plan first to calcine it, that is, to make it red hot in the fire, and then quench it with strong red vinegar, and grind it a little at a time on a porphyry slab. This, tempered with clear water, makes a beautiful red for painting in fresco; but, as this stone is not very common, and as it is very difficult to reduce to powder, it is not much used by painters; but there is none of it but what makes a beautiful colour like lake, for painting in fresco, and it is very durable.”
The next author I shall quote is Baldinucci. (Voc. Dis. Tit. Amatita, Lapis Amatita, Matita). The following are extracts: – “Amatita, a soft stone like gesso, with which drawings are made; there is some black and some red. See Lapis Amatita and Matita.” “Lapis Amatita, Matita, otherwise called Mineral Cinnabar, a very hard natural stone, used by painters to make designs on leaf gold, where it leaves its colour, which is red. This being ground, although with great difficulty on account of its hardness, makes a beautiful colour, like lake, which serves for painting in fresco, and which is very durable. The sword cutlers use it for burnishing gold.” Again, “Matita, a kind of soft stone used by our artists in drawing. It is derived from the Greek word hæmatite, because it has the colour of blood, which they call hæma.” Again, “Matita Rossa, a kind of soft stone, brought to us in pieces, which are sawn with an iron saw, and reduced to a point, which serves to draw upon white and coloured paper. The best comes from Germany.”
“Matita Nera, a sort of black stone, which comes to us in small pieces, and which are reduced to a point by scraping with a knife; it is used to draw on white and coloured paper. It is also dug in the mountains of France, and other places, but the best comes from Spain.”
De Piles, in his Elémens de Peinture, speaking of colours used in fresco, observes, –“Rouge violet is a natural earth, produced in England, and employed in fresco painting instead of lake: and the fresher the mortar is, on which this pigment is used, the more beautiful is the colour. The ancients had another colour, which was very proper for this kind of work and which very nearly approached lake, but its composition is unknown to us. Some think that it was a kind of minium.”
The Spanish painter and author, Pacheco (page 366), speaks of the red pigment used instead of lake in fresco, by the name of “Albin.” This author says, “The Almagre de Levante supplies the place of vermilion, in flesh and light red draperies, and Albin the place of carmine.”
The next author I shall quote, is the Spanish author Palomino, who, in vol. 2, page 148-149, says, “Albin and Pabonazoa are mineral colours, and are used in fresco painting, only tempered with water. Albin and Pabonazo do not change, and are colours which supply the place of carmine so well, that, being used on very fresh stucco, they have sometimes deceived people, appearing to be carmine; and, observe, that Pabonazo is a degree lower in tone than Albin, and this is not sold in shops, but is procured from the mines of copper in the kingdom of Jaen; and there, and in all Andalusia, painters and gilders esteem it much, and it is even sold under the name of Almagre.” Again, “The crimson in fresco painting, is to be Albin and Pabonazo.” II. Palom. page 151.
a There are artificial pigments called in Italian Pavonazzo, which cannot be used in fresco.
The last, and in point of date, one of the earliest of the modern writers on the arts, Eraclius,b whom I shall quote, and whose work is still preserved, mentions the substance as affording a red pigment, although he does not limit its use to fresco painting. In speaking of purpurinus, he says, “And indeed glebæ or flints, that is, stones emitting fire, seem very necessary in painting, when they are heated in the fire, and are quenched by having very strong vinegar poured over them; and they produce a purple colour.”
b De Artibus Romanorum. Eraclius is supposed to have lived between the 7th and 13th centuries, since the latest author he quotes is Isodorus, who lived in the 7th century. See Raspe on Oil Painting, p. 45. –The copy of this author’s work published by Raspe is very imperfect; that which is preserved in the Bibliothèque Royale at Paris, contains many additional chapters and much valuable information on early methods of painting, and substances used in the Art.
And in chapter 266, Eraclius again mentions the same stone in the following extract: – “How a stone and the tooth of an animal is polished. Take the stone which is called emantes, which should not be too hard, nor veined, but very smooth and bright, and go to a workman’s grindstone, and make it as flat as you like. And when it seems sufficiently ground, rub it still smoother upon a tile, and then, in order to make it finer, with a whetstone. Afterwards polish it upon a leaden table.” – Extract from a MS. of Eraclius in Bib. Royale, Paris.
It will be observed that there are two kinds of stone noticed in the above extracts, the hard and the soft; I shall endeavour to prove, firstly – that the Amatito of Cennino, and the Albin of Palomino, are a variety of the Hæmatite; secondly – that the Lapis Amatita was, and is the stone commonly used to burnish gold; thirdly – that Amatito is not mineral Cinnabar; and fourthly – that Pabonazo is the Matita Rossa. But it will be necessary, previously, to ascertain the properties of these minerals, as described by these authors, and of the Red Hæmatite as described by the writers on mineralogy.
FIRSTLY, THAT ALBIN AND AMATITO ARE A VARIETY OF HEMATITE. – It appears from the preceding extracts, that Amatito was a natural red pigment, prepared from a very hard and firm stone – that tools were made of it to burnish gold – that it took a good polish – that it had striæa or fibres like Cinnabar – that it was so hard as to require to be broken in a bronze mortar, or calcined before it was ground, lest it should break the porphyry slab—that it made a lake or crimson coloura—that it could only be used in frescob—that the colour was so fine as to be distinguished with difficulty from lake and carmine—that it was brittle and should not be suffered to touch iron—that its colour was not injured by fire, since Borghini, and Eraclius, direct it to be calcined, in order to grind it more easily; nor by acetic acid, since the same writers also direct the red hot stone to be quenched in strong red vinegar—that the reasons for discontinuing its use, were, its scarcity in Italy, and the difficulty in grinding it—that this colour is mentioned by almost all the above authors as being very durable.
a Tiglio and Vena, the Italian terms for striæ, although apparently synonymous are not so, since the Dizionario, of Alberti, does not refer from one to the other and since Cennino uses both. Tiglio seems to mean veins or streaks of the same substance, as in wood, ivory, &c., and vena has the same meaning, and also signifies veins of other substances, included in a mineral, as veins of gold in Lapis Lazuli, &c. The term Tiglio seems to correspond with the term striæ rather than vein. The stone was to be without veins of other materials.
a Purple. The terms Pabonazo, Pavonazo, Purpura, Porpora, were not used formerly to denote the colour we now call purple, but merely a red inclining to blue, namely crimson or lake colour. Pliny, (Nat. Hist. Book 31, chap. 33, Holland’s translation,) describing the Syrian purple, says, “It is thought to have a most commendable and excellent dye, when it is as deep a red as blood that is cold and settled, blackish at the first sight; but look between you and the light it carrieth a bright and shining lustre. And hereupon it is that Homer calleth blood, purple.” Cennino himself proves that he meant by Amatito, a crimson and lake colour and not a purple, as appears from the preceding quotations from chap. 42 and 136, and also from a passage in chap. 74, where he says, “If you would make a purple colour to be used in fresco, take Indigo, and Amatito, and mix,” &c. He uses the word “bisso” when he means to express a mixed colour of blue and red. See chap. 74, 78, 79, 145, and the note by Sig. Tambroni, who concludes by observing, “The ancients imitated the porpora (dye from the fish called porpore), by mixing porporisso with blue, and the moderns, to supply the place of porporisso, use lake.” See Goethe on Colour, by Eastlake, p. 244, 279. Borgh. Rip. 189.
Albin also was a lake or crimson colour, because Palomino, (vol. 2. p. 150) adds smalt to it to make it a morella colour. See also Pach. 366, II. Palom. 151, where he says it is used in fresco instead of Carmine.
b It is proper to notice here that Leonardo da Vinci (Trattato della Pittura, Chap. cccliii, Milan edition, by Amoretti,) in describing the method of painting on linen cloth (tela), observes, “The flesh colour should be white lead, lake, and Naples yellow; the shade should be black, majorica, and a little lake, or if you please lapis duro.” Diego Antonio Rejon de Silva, the Spanish translator of Leonardo’s Treatise, who used the edition of Leonardo’s work published in France by Du Fresne, calls the colours for the shadows, black and majorica, and lake or lapis roxo. He observes in a note on this passage, “The signification of the word majorica is not to be found in any dictionary.” I shall have no difficulty in proving that this majorica is the soft red hæmatite, and that it derived its name from the Island of Majorca, whence it was brought into Italy. I have now transcribed the passage, for the purpose of shewing that the “lapis duro” or “lapis roxo,” which I shall prove to be the hæmatite, was used by Leonardo da Vinci in painting on linen. But this is no proof that it was an eligible pigment, and durable in this kind of painting, because Leonardo was fond of making experiments (which there is no doubt the method described in this and the preceding chapters were) and because many of Leonardo’s colours were known to have faded considerably. See De Piles, Lives of the Painters, p. 107.
It is somewhat curious to observe the manner in which the passage has been translated in the English edition, by M. Rigaud of the Royal Academy, re-published by Mr. J. W. Brown in 1835, p. 130. “The shades with black, umber, and a little lake, you may if you please, use black chalk.” Thus getting rid of the incomprehensible word “majorica,” (the Pons Asinorum of the Spaniard,) and the lapis duro; changing the majorica, which is red, into brown; and the lapis duro, which is red also, into black. Umber is always rendered in Italian by “Terra d’ombra,” and black chalk by Matita Nera.
The original passage is expressed thus by Leonardo, “l’ombra sarà nera, majorica, e un poco di lacca, o vuoi lapis duro.”
There is no doubt that P. Lomazzo, the personal friend of L. da Vinci, alludes to this practice of da Vinci’s in the following extract from the Treatise of the former (Book iii, chap. xiv, p. 292), “Per acquerella e per disegnare in carta, per il nero vè l’inchiostro, la pietra tedescha, la terra nera, et il carbone di salce, o’ del roncagino; per il rosso, la pietra rossa detto apisso la quale era usatissima da Leonardo da Vinci.” I have not been able to find in any dictionary or work on art a description of a red stone called “Apissa,” but the same word also occurs in the “Idea del Tempio della Pittura,” (p. 71,) where Lomazzo calls the stone used for drawing (which other writers call “matita”) Carbone Apissa.
It also appears, from the preceding extracts, that Albin was a mineral, which supplied the place of lake, and was used principally in frescoa – that Matita Rossa was a soft stone, – that Pabonazo was a degree lower in tone than Albin, was procured from copper mines, and was used by painters and gilders, to whom it was known by the name of Almagre.
a Pacheco indeed, p. 390, states that some painters used for draperies in oil Almagre de Levante or Albin, shading them with carmine and black.
The following extracts are the characteristics of Hæmatite given by mineralogists.
Georgius Agricola gives a minute description of the varieties of the Hæmatite. He says, that the Hæmatite produces the Rubrica, (p. 64. of the Venetian edition in Italian) – that it is of the colour of blood (p. 168), – that being ground on the grindstone it yields a red juice, while the Schist (another variety), gives more frequently a yellow juice (p. 175), – that it is found also in iron mines, but more frequently in veins alone – that the Hæmatite and the Schist differ in appearance, the latter being easily split in a particular direction, and its fibres being arranged in such a manner as to resemble congealed wood – that the Hæmatite and Schist are produced in many parts of Germany and also in Spain and other places – that where the Hæmatite is found, there is also found the Terra Sinopide. He adds, that the Schist is sometimes dull externally but sparkles internally, like artificial Minium, and that painters call it also Cinabrio, and that this kind is found in the Black Forest – that the Schist and the Hæmatite, being like congealed blood, whenever they are burnt, or calcined, imitate the colour of Cinnabar – that the Schist has the same colour as the Hæmatite, that the best Hæmatite is that which has the colour of congealed blood, which is diffusible in water, which is equally coloured throughout, which is pure, (p. 251, 253). By the term Schist he evidently designates the Lapis Amatita, and by Hæmatite, he means the softer kind mentioned in the next chapter.
The French Encyclopædia describes the Hæmatite as “une pierre, ou plutôt une vraie mine de fer dont la figure varie, son tissu est tantôt strié ou par aiguilles, comme l’antimoine; tantôt il est composé de filamens ou de fibres, qui à la couleur pres, la font ressembler à du bois, (wood iron,) tantôt elle est sphérique ou hémisphérique, tantôt elle est en mamelons, et formée par un assemblage de globules qui la font ressembler à une grappe de raisins; tantôt elle est garnie de pyramides et de pointes; tantôt enfin elle parait composée de lames ou de feuillets qui laissent quelquefois des intervalles vuides entr’eux, et la font ressembler à un rayon de miel. L’Hæmatite varie aussi pour la couleur; il y en a de rouge, de pourpre, de jaune, et de noiratre ou couleur de feu, mais lorsqu’ on l’ecrase, elle est toujours d’un rouge ou d’un jaune plus ou moins vif. L’Hæmatite, quoique fort chargée de fer, n’est point altérable par l’aimant, le fer qu’elle donne est aigri et il est difficile de lui procurer la ductilite convenable; il y en a dont le quintal contient jusqu’ á 80 livres de ce metal. Voilà pourquoi quelques gens l’appelent Ferret.” – Encyc. Franc. Art. Hæmatite.
Pliny enumerates five kinds. – The five sorts differ chiefly in point of hardness. The best, according to Dioscorides, is that which is hard, black, and smooth, without either gritty parts or veins.
“That commonly used by the painters is factitious, being made of Armenian bole, and other drugs. The common native or the fossil kind comes from Bohemia, &c. This assumes various forms: – spherical, pyramidal or cellular, and is composed of small pyramids; the apices of which appear in a tranverse section in the centre. It contains a large portion of iron, but the iron is obtained with such difficulty and is of so bad a quality, that this ore is not commonly smelted. This stone, when exposed to a moderately strong fire, falls by degrees into scales, and in this state is attracted by the magnet, and gives out its iron to acids. The gilders use it for burnishers to polish their metals. Bauschius has an express treatise, on the Lapis Hæmatites.” – See Chambers’ Dictionary.
The following is Jameson’s description of Red Hæmatite or Fibrous Red Ironstone. Its colour is usually intermediate between brownish red and dark steel grey. Some varieties incline to blood red, others to dark steel grey, and others to bluish. It occurs most frequently massive and reniform; also botryoidal, stalactitiform and globular. The external surface is generally rough and glimmering, seldom smooth and shining. Internally it is usually glistening, which sometimes passes into glimmering and the lustre is semi-metallic. The fracture is always fibrous, and is straight, delicate and stellular or scopiform. The fragments are commonly cuneiform, seldom as in the coarse sorts, fibrous or splintery.
It generally occurs in distinct concretions, which are large, small or fine, angular, granular and traversed by others which are curved, lamellar more rarely, it occurs in cuneiform prismatic concretions. The surface of the concretions is either smooth or streaked, and the colour inclines to iron black, with a shining and metallic lustre. The streak is always blood red; it is hard, passing into semi-hard; it is brittle; it is rather easily frangible; it is heavy, inclining to uncommonly heavy. Specific gravity, 4.740, Gellert; 5.005, Kirwan; 4.8983, Brisson; 4.840, Wiedemann; 5.025, Ullman.
Its constituent parts consist of – Oxide of Iron, 90; Trace of Oxide of Manganese, 0; Silica, 2; Lime, 1; Water, 3; = 96. – Daubuisson, Ann. de Chimie, 1810.
It occurs in every situation where the compact subspecies is found, and like it in veins, beds, and lying masses (liegende stocke), that approach in magnitude to mountain-masses; principally in primitive mountains, but also in transition, and floetz mountains. The different subspecies frequently occur together, both in beds and and in veins. In veins it is the compact and ochry that predominate; the hæmatite occurs principally in drusy cavities, the walls of which are encrusted with the scaly subspecies.
It occurs in veins that traverse sand-stone, at Cumberhead, in Lanarkshire; in veins in floetz green stone, at Salisbury-Craigs, near Edinburgh; at Ulverstone, in Lancashire; in Cumberland, and also in Devonshire, and near Bristol, in Gloucestershire. It is found in considerable quantity in Saxony, from Berggieshubel to Voightland; in Bohemia, but not so abundantly as in Saxony; at Bareuth, Wolfstein, in the Palatinate; Silesia, Lauterburgh, Walkenried, Andreasberg, Wernigerode, in the Hartz; and Salzburgh; in Siberia, and in Mexico. It affords excellent malleable and cast iron; and, when ground, it is also used for polishing tin, silver, and gold vessels, and for colouring iron brown.
The name Hæmatite which is derived from the Greek αιμα, sanguis, was given to this ore of iron, from its red colour. With respect to its geographical situation, it is to be observed that it occurs in great quantity in the kingdom of Saxony, less abundantly in the east side of the Hartz and Bohemia; not so abundantly in the Fichtelgebirge, and in considerable quantity in Norway, Sweden, Poland, Hungary, and Russia. In England it occurs particularly abundant in Lancashire. It is found in considerable quantity in Devonshire and Cornwall, and is one of the most common species of iron stone. – See Jameson’s Mineralogy, tit. Red Hæmatite.
The description by Phillips and Ure, and other writers of the “Fibrous Red Iron Ore, Hæmatite,” and “Compact Red Iron Ore,” so closely resemble those which I have extracted from Jameson, that it would be useless to repeat them. It will be sufficient merely to refer to Phillips’ Mineralogy, p. 229, 230, third edition, and to Ure’s Dictionary of Chemistry and Mineralogy, Art. “Ores,” also to the Penny Cyclopædia, Art. “Iron.”
On a careful perusal of these descriptions, it will be seen that the Red Hæmatite resembles in many particulars the pigment described by the various writers on art. Thus it is stated, that Red Hæmatite resembles the Lapis Amatito in the following particulars: – The colour, externally, was bluish, or iron grey, sometimes red, or black, (Phillips, Jameson, Penny Cyclopædia, Cenn. Bald. Agric.). – It was hard, smooth, without veins, or gritty parts, (Dios. Pliny, Jame. Cenn.). – Its structure was fibrous. (Enc. Franc. Phil. Jameson, Penny Cyclopædia, Agric. Cenn.). – When calcined it fell into scales. (Pliny, Borg. Erac.). – It was brittle. (Ure, Jame. Cenn.) – Gilders used it for burnishers to polish their metals. (Jame. Cenn. Bald.) – In this last particular writers on Mineralogy differ from the writers on Art; Phillips and Ure say the powder is used to burnish metals; Jameson does not particularize, but merely observes, of the Red Hæmatite, that “it is used for polishing tin silver and gold vessels, and for colouring iron brown,” while the writers on art assert, that the solid stone, when shaped into a tool and polished, was used to burnish metals. It was fibrous like cinnabar, which it resembled in colour, and by which name it was also known. – (Cenn. Agric. Bald. Borg.)
With respect to the Albin of Palomino, the description is more indefinite than that of Amatito. In the index of the Terms of Art, added by another writer to the first volume of Palomino’s Museo Pictorico, (third edition, 1795,) the following explanation is given of Albin; “a dark crimson colour which is brought in stones (Piedras) from the mines of copper; it serves instead of carmine for painting in fresco.” In Gattel’s Spanish and French Dictionary, Albin is thus explained, “Sanguine; pierre de couleur rouge. Lat. Lapis Sanguinarius. Couleur rouge faite avec la sanguine. Lat. Color ex lapide sanguinario.” In Pineda’s Spanish Dictionary, Albin is translated Bloodstone.
It may be proper to mention, that there is a mineral called Albin, mentioned in Phillips’ Mineralogy, p. iii, of an opaque white colour, from which indeed it derives its name. It has none of the properties of the Albin of Palomino.
SECONDLY, THAT LAPIS AMATITA – RED HEMATITE – WAS USED TO BURNISH GOLD. – I shall now endeavour to prove that the Lapis Amatita, the Red Hæmatite, was and still is used to burnish metals. It is unnecessary to repeat the extracts already given from Cennino, Borghini, and Baldinucci. These authors have proved that the Lapis Amatita was used as a burnishing tool; I shall now prove that the Hæmatite was formerly, and is at the present time, used for this purpose, and thus establish their identity.
Eraclius calls the stone used in polishing “Emantes.” Theophilus, in his Treatise on various Arts, chap. xxxi, says, “polies illud dente vel lapide sanguinario diligenter limato et polito super tabulam corneam æqualem ac lucidam,” – translated, – “You must polish it with a tooth, or with a bloodstone, lapide sanguinario, carefully filed and polished upon a smooth and shining horn table.” The author of the additional chapters appended by Raspe to the first book of Theophilus, directs that gold should be burnished with “emate,” and in cap. xxxv. says, “Deinde limpidissima petra vel onychino aut emate vel simili re convenit scripturam detergere, quod sic et soliditatem accipit et fulgorem vel colorem,” i. e. – “It is then proper to clean the writing with a very transparent stone, or with an onyx, or with emate, or with some such thing, and thus it receives both solidity and brilliancy or colour.” M. Le Comte Charles de L’Escalopier adds by way of note to the first of these passages, “scribendum videtur hic et e. 35 ematite,” – “I think it should be written ematite both here and at cap. 35.” He also adds in another note on the word emate “Nous ne doutons pas qu’il s’agisse de la sanguine, lapis sanguinarius, qu’il ne faille lire ematite.” Hæmatite, (Theoph. p. 290). Benvenuto Cellini (Opere, vol. iii. p. 14,) polished gold “pigliando un amatita nera (dark) che son quello che adoperano gli spadai metter d’oro.” This passage immediately recalls the beforementioned expressions of Borghini and Baldinucci. M. de Brongniart (Traité des Arts Céramiques, &c., p. 646,) informs us that in the manufactory of porcelain at Sevres, gold is still burnished with the “hæmatite dure,” which the workmen call “sanguine.” And in the Magazine of Science, vol. i. p. 206, it is said, “Bloodstonea is a very hard compact variety of hæmatite iron ore, which, when reduced to a suitable form, fixed into a handle, and well polished, forms the best description of burnisher for producing a high lustre on gilt coat buttons, which is performed in the turning-lathe by the Birmingham manufacturers. The gold on china ware is burnished by its means. Burnishers are likewise formed of agate and flint, the former substance is preferred by bookbinders and the latter for gilding on wood, as picture frames, &c.”
a There is another mineral called Bloodstone, namely the heliotrope or quartz, jaspe-sanguin of Haüy. “It is mostly of a deep green colour, and commonly yellow or blood-red spots are interspersed through its substance. From the latter circumstance it has obtained the name of Bloodstone.”—Phillips’ Min., p. 15. By this colour it is sufficiently distinguished from the Hæmatite.
Vasari (Intr. chap. xxxii.) likewise mentions the stone by the name of “Matita dura,” which when ground, was to be used with the Matita rossa, and another colour prepared from “scaglia di ferro,” for painting the shades of flesh on glass.
This certainly does not agree with the assertion of Cennino, that Amatito could not be used in any kind of painting but fresco; but as he does not treat of painting on glass, this does not invalidate his testimony, because this art was not practised to any extent in Italy until the time of Giulio 2. who sent for William of Marseilles to paint windows for him at Rome, (see Seroux d’Agincourt, Histoire de l’Art par ses Monumens, Peinture, vol. 2, p. 143. Le Vieil, De la peinture sur verre, p. 18. Vasari, vol. 5, p. 187). Cennino therefore could not have been acquainted with this description of painting.
THIRDLY, THAT AMATITO IS NOT MINERAL CINNABAR. – I have now to prove that Amatito is not mineral cinnabar as asserted by Borghini, and as De Piles supposed.
We have already observed, that Geo. Agricola says, that the stone which he calls Schist (after Pliny), resembled in its appearance minium, and that the painters called it cinnabar; that when calcined it imitated the colour of cinnabar.
Baldinucci, who had seen Cennino’s Treatise, probably derived much of his information from that work, and much from common tradition, since, although he was an excellent draftsman, he did not paint. (See Lettere sulla Pittura, vol. 2, p. 392. n.) We have also his distinct assertion, as before quoted, that the true derivation of lapis amatito was lapis hæmatitos, meaning stone of a blood-colour.
Raphael Borghini, though descended from painters on the mother’s side, and intimately connected with the painters and sculptors of his time, was not a painter himself; he was not, therefore, likely to be acquainted with the practical details of painting. In the second book of the Riposo, he has borrowed largely from Cennino. In many cases he has given a literal version of Cennino’s text, and in others quite a paraphrase, although without having the honesty to acknowledge whence he derived his information; indeed it is remarkable, as Sig. Tambroni observes in the preface to Cennino’s Treatise, that Borghini does not once mention Cennino’s name although it is evident, he had read great part of his work. Cennino does not assert that Amatito was mineral cinnabar, his expression is merely, “ha un tiglio come cinabro.”
In the note to chap. 42. of my translation of Cennino’s Treatise on Painting, I have expressed an opinion, that Amatito was mineral cinnabar, but having since investigated the subject, I am convinced that I was mistaken.
At first sight, the resemblance between the two minerals is sufficiently striking to warrant the conclusion. The colours of both varied between dark grey and red, both are fibrous, and yield a red powder when pulverized; but, there the resemblance ceases; Mineral Cinnabar is soft,a Amatito is hard: see the descriptions of native or Mineral Cinnabar in Ure, Phillips, and Jameson. Moreover, Amatito can only be used in fresco, Cinnabar is incompatible with lime.
a Pliny indeed speaks of a kind of native Cinnabar brought from Spain, but he adds, that “it was hard and full of sand,” and that also brought from Colchis was hard “and not better than that of Spain;” and he evidently disapproved of both kinds. – Book xxxiii, p. 325.
The best proofs, independently of the direct assertion of Geo. Agricola, before noticed, are, however, to be derived from the works of writers on painting.
Borghini (Riposo p. 167) says, that Cinnabar was first procured from the quicksilver mines of Spain. He afterwards gives a recipe for making artificial Cinnabar. He adds that both kinds were used for painting in oil.
Paolo Lomazzo, in his treatise on painting (Lib. 3, Chap. 4) mentions two kinds of Cinnabar, namely, the mineral or native, and the artificial. In the same chapter he enumerates among the artificial pigments, Cinnabar, except the native Cinnabar (il cinabro eccetto quello di miniera). In chapter 6, he informs us, that the artificial Cinnabar was inimical to lime, (è nemico della calce). The only red named by this author, proper to be used in fresco, is Majorica. By this we find, that Amatito was no longer in use. The treatise of Lomazzo was published in 1584, the same year as the Riposo of Borghini.
Palomino, after naming certain colours to be used in fresco, adds, “and vermilion, although the native or mineral, is better than the artificial vermilion.” But he says that in uncovered places, and in such as are exposed to the inclemency of the weather, neither the native nor artificial should be used, because in a few days they both lose their beauty and turn to a dull mulberry colour. But in covered situations, and those defended from the weather, it is a beautiful colour and very permanent. But in order to make it more permanent, it should not be laid immediately upon the stucco, which should be previously dead coloured with tierra roxa, and the vermilion should be laid over this, making it lighter with white, and darkening it with albin and pabonazo, and in some of the deepest shadows adding sombra del viejo or tierra negra, and it will remain so fresh and beautiful, that even with oil colours it could not look better.” – 2 Palomino, p. 149.
This shews that vermilion and albin were different substances, since the vermilion was to be shaded with albin.
The author of the Vocabulary of Terms of Art, added to the work of Palomino before mentioned, names both the native and artificial vermilion. The native or mineral vermilion, he says, is of a red colour, procured from quicksilver mines.a It will perhaps be recollected that he had informed us that albin was procured from copper mines. The former, he says, was good for painting, (using the term generally,) – the latter, for painting in fresco. It is quite evident that he did not consider the terms synonymous.
a Palomino, (vol. 2, p. 340.) also informs us, that native Cinnabar was procured from quicksilver mines.
Alberti (Dizionario Enciclopedico), following Baldinucci, (Tit. Cinabro Minerale,) says “mineral cinnabar is called by some lapis amatita.” He adds, of the true native or mineral cinnabar, it is a mineralized ore of mercury, fibrous or smooth, of a red colour and shining.”
Vitruvius also remarks that minium (cinnabar) would not stand 30 days in places exposed to the light and weather, (Vitruvius Liv. 8. Chap. 9.), and was always covered with wax and oil. In this he has done little more than repeat the words of Pliny (Book 33).
It is unnecessary to quote all the writers on painting who have said that cinnabar is inimical to lime, or to revert to the method adopted by Pozzo to render it permanent in fresco, since he does not mention, whether he used the native or artificial. I cannot discover that any writer on painting, except Pozzo, recommends using cinnabar on the wet lime in fresco.
From the foregoing extracts and observations, I trust I have established the fact, that painters formerly possessed a natural red pigment for painting in fresco; and that this pigment was not mineral cinnabar.
FOURTHLY, THAT PABONAZO IS THE SAME AS MATITA ROSSA, and that the names of Sinopia, Majorica, Terra Rossa d’Inghilterra, Bruno d’Inghilterra, Ferretta di Spagna, and Almagra, hereafter mentioned, are only different names for the same mineral colour, which I think will be found fully established in the subsequent part of this work treating of Sinopia.
I shall now show that Amatito and Albin were not the “vetriuolo cotto o abbrucciato” of the Italian writers.
Amatito and Albin were, as I have shown, natural pigments, which required merely to be pulverized to constitute a fine pigment for fresco painting. Vetriuolo cotto or abbrucciato is, on the contrary, an artificial pigment, prepared by calcining sulphate of iron, by which process it acquires its red colour.a
a The sulphuric acid is expelled by heat, and a per-oxide of iron remains in the vessels. It has been before observed that the Hæmatite contains in addition to the iron, silica, &c., traces of manganese and lime.
It was unknown to or at least not mentioned by Cennino, but is mentioned by Lomazzo and Borghini whose works were published in 1584, and by succeeding writers. It is called vitriol calciné by De Piles, (Elémens de Peinture, Jombert’s Edition), vitriolo Romano quemado by Palomino; vitriolo calcinado, in the Spanish vocabulary of terms of art before mentioned, and burnt Roman vitriol by the English.
It is said by Pozzo to be a beautiful colour like lake for fresco, but it is obvious, that if a natural pigment can be procured, the colour of which is equally fine, it must be preferable for painting in fresco.
The Amatito of Cennino was not the amethyst. The lightness and want of body of the colour of the latter, and the fact of that colour being violet and not lake, sufficiently prove that the two substances are not synonymous.
It is mentioned in the first Report of the Commissioners on the Fine Arts p. 28, that Prof. Hess uses oxides of iron for red pigments in fresco. It would be desirable to ascertain the exact species.
In conclusion, I would observe, that the red Hæmatite contains nothing in its composition incompatible with lime and with the pigments used in fresco painting; that lime is a constituent part of it; that the ore is found in several parts of England, and in great abundance at Ulverstone, in Lancashire, where it occurs in an enormously thick vein, traversing limestone (see Phillips). That the difficulty of grinding can be no objection to its use, since pigments are now ground in a mill purposely constructed, and that it is most important to the practice of fresco painting, to acquire a permanent pigment of a lake colour; that Amatito is not a new pigment now attempted to be introduced for the first time, but one which has been tried and approved. It may also be observed, that the colours produced from iron are always permanent, the natural more so than the artificial, and that such pigments are of universal application in painting.
I stated the characteristics of Amatito to Mr. Tremayne, of Heligan in Cornwall, and to his kindness, I am indebted for a copious supply of two species of red Hæmatite, from a mine in the parish of Roche in Cornwall, the hard and the soft; and I caused a specimen of the hard Hæmatite to be pulverized, and having washed some of the powder, and poured off the lighter particles, I found a portion of iron had sunk to the bottom, the removal of which seemed to render the colour finer. I also calcined another portion of the stone, and found it separated into scales, in the manner described. The colour of the stone when calcined, varies from lake to violet, according to the length of time it is exposed to the fire; and this agrees with the statement of Dr. Lewis, inserted in the Encyc. Brit. Art. colour-making.a
a His words are as follow: – “The oxides of iron may be made to appear purplish, or inclining to the scarlet, according to the manner in which the calcination is performed. If the matter is perfectly deprived of its phlogiston, and subjected to an intense fire, it always turns out red; but the mixture of a small quantity of inflammable matter, gives it a purplish cast.”
It is remarkable that the oxides of iron never shew their proper colour till they are cold.
The fibrous red Hæmatite of Ulverstone, has a finer grain than the Cornish.
OF SINOPIA.
Besides the Amatito and Albin before mentioned, writers on art mention other natural red pigments proper to be used in fresco, namely, Rubrica, Sinopia, Cinabrese, Majorica, Terra Rossa d’Inghilterra, Terra Bruna d’ Inghilterra, Rouge Violet, Ferretta di Spagna, Almagre, Pabonazo, Tierra Roxa, and Burnt Ochre, are all spoken of by different authors as red colours, or used instead of red colours, and are all ores of iron; and, excepting the last two, are merely different names for the same pigment, differing merely in quality, intensity of colour, or mode of preparation. That this pigment is in fact the Hæmatite or red ochre of the mineralogists. – See Phillips, Jameson, Tit. Red iron ore – Hæmatite.
Sinopia is mentioned or referred to as a red colour by most of the several writers on colours and pigments. It is described by Pliny as a natural pigment, which derived its name from Sinopia a city of Pontus, it was also brought from Egypt; the Balearic Islands, (Majorca, Minorca, &c.) and Africa; but the best was brought from the Isle of Lemnos and Cappadocia, where it was found in certain caves and holes. That which adhered to the rocks was the best, and the pieces of which on being broken, shewed the same colour throughout. There were three sorts differing in colour. The first deep red, the second paler, and the third browner. The Lemnian earth, called also Terra Sigillata, was considered next in value to Minium (vermilion), and none was allowed to be sold without having been previously marked with the seal of Diana (a goat, the Turkish seal was afterwards substituted for this), for which reason it was also called “Sphragis.” The painters ordinarily laid a ground of this under vermilion, and sophisticated it in many ways. – See Pliny, Book xxxv.
Dioscorides says, this red ochre of Sinopia is very fine: it is heavy, dense, and of the colour of liver without any mixture of stone; it is equally coloured throughout, and if put into water diffuses itself equally.
Geo. Agricola says, that the earth which the Greeks call Milto, because it is red, is called Rubrica. This is found in mines of gold, silver, copper, and iron, as Theophrastus writes; and it is often found in veins by itself. He adds, that the best kind is brought from Sinopia, and next to that is the earth of Lemnos, where, among the threea species of earth which (as it is said) were found in a heap, (tumuletto) was the rubrica fabrile.b He mentions, that in addition to the places named by Pliny and Dioscorides, it is also found in Germany, and according to Strabo, in Spain, and that this last kind was in no degree inferior to Sinopia. That there were three kinds of Rubrica, the first soft, which stained the hands; the second less soft, which stained less; the third was hard, and was called stone (sasso), which did not stain the hands unless they were wet. This last, I consider to be the Lapis Amatita, the fibrous red Hæmatite, the Glebæ of Eraclius, the Albin of the Spaniards. He adds, that all three kinds were used by painters. (Book ii. p. 202.) The pale coloured Rubrica is probably Armenian Bole.
a One species of earth appears to have been the Rubrica, another Bole, the third white, the last two were Argillaceous.
b Rubrica fabrile. This proves the pigment to have been an ore of iron, since the term fabbrile or fabrile is applied to working in iron – which is called L’Arte fabbrile.
Cennino says, “there is a natural red pigment called Sinopia or porphyry, that this colour is naturally transparent and drying. It bears grinding well, and the more it is ground the better it is. It is good for painting either on pictures or walls in fresco or in secco.” Cenn. Chap. 38.
Sinopia is mentioned by Borghini (Riposo p. 166), incidentally, when speaking of cinabrese. He describes it nearly in the words of Cennino, who mentions it as a red colour called light cinabrese, and composed of two parts of Sinopia and one of Bianco Sangiovanni, (a white made of very white and pure lime.) These two pigments were therefore prepared from the same mineral.
Requeno, a learned Spaniard resident at Rome, in his work written in Italian, entitled Saggio Storico sul Ristabilimento dell’ Antica Arte de’ Greci e Romani Pittori, (vol. 1. p. 258.) commenting on the colours used by the ancients, observes respecting Rubrica, that “this was our mineral red earth. Vitruvius cites that of the Island of Majorca in Spain among the finest sorts, and I have always thought that the ancient Rubrica might be the fine Spanish Almagre.”
The only red pigment mentioned by Paul Lomazzo (Trattato della Pittura, p. 191, 192.) as proper to be used in fresco was terra rossa detta Majorica.a The descriptions of Pliny, Theophrastus, and Geo. Agricola, prove that Sinopia was brought from Majorca, one of the Balearic Islands.
a The beautiful vases of Majolica, of which Cennino speaks, (c. 107.) were probably so called from their having been formed, or at least, principally coloured with this mineral. – See “Traité des Arts Céramiques par. M. de Brongniart.” Vol. ii. Page 55-59.
The terms Rosso d’ Inghilterra, Bruno d’ Inghilterra, and Rouge Violet appear synonymous, or nearly so. Pozzo says that this colour (always supposing them synonymous), when used on very wet lime, appears like lake when dry. Malvasia (Felsina Pittrice, vol. i. p. 349) says, that Bruno d’ Inghilterra was much used then, i. e. in the latter part of the seventeenth century, in fresco, instead of lake.
Pacheco (Tratado de la Pintura, p. 366) directs Almagre de Levante to be used instead of Vermilion for flesh tints and light draperies in fresco. In p. 350 he says, that this colour is admirable in all kinds of painting. It will be observed this author calls the pigment “Almagre de Levante,” an additional reason for supposing it to be Sinopia.
Palomino (vol 2, p. 149) enumerates among the mineral colours used in fresco painting, Albin and Pabonazo, which he says do not change, and supply the place of carmine so well, that when used on very wet stucco, they have often deceived people, appearing to be carmine. He adds that Pabonazo is one degree lower in tone than Albin, and that it is not sold in shops, but is brought from the copper mines in the kingdom of Jaen, and there, and in all Andalusia, it is much valued by painters and gilders, and is even sold under the name of Almagre. This passage identifies Pabonazo with Almagre.
I think it will appear, from the preceding extracts, that the pigments called Majorica, or Majolica and Almagre, are of the same nature as Sinopia. But it is probable the latter was the finer colour; since Pacheco always distinguished it by the name of Almagre de Levante, thus shewing the similarity of its nature, and a preference for the oriental pigment, although, as before mentioned, Strabo says, that the kind produced in Spain was not inferior to the true Sinopia. Palomino has distinctly informed us that Pabonazo was also called by the Arabic name Almagre. It is probable that Sinopia was superseded by Terra Rossa d’ Inghilterra in Italy, since P. Lomazzo does not mention Sinopia, and by Pabonazo or Almagre in Spain. Georgius Agricola, speaking of the colour called Armenian blue, observes, that it had been very scarce since the Turks had been masters of the country. The same influence may also have prevented the introduction of Sinopia into Europe in sufficient quantities for the use of painters, and occasioned them to have recourse to the productions of other countries for their pigments.
The French translator of Pliny mentions that a kind of Bol d’ Espagne, called vermilion, was sold about 1725. Benvenuto Cellini mentions (Opere. vol. iii. p. 145.) among ingredients used to give a colour to gold, “Ferretta di Spagna;” now Ferretta di Spagna, or Ferretta simply, is a kind of Hæmatite which is a true ore of iron (see Alberti Diz. Enc.) There is also an artificial kind described by Neri, (Art. Vit.) made by calcining copper with sulphur. I merely mention this fact to shew that the two were not synonymous. The appellation Ferret was applied by the French to the Hæmatite.
The soft species from Cornwall, which appears to be formed from the decomposition of the harder species, and which I have examined, is heavy, dense, of the colour of liver, without any strong or gritty particles, equally coloured throughout, and when put into water, diffuses itself equally, but afterwards settles at the bottom of the vessel. It will be observed that the several kinds of Hæmatite are found generally together; on referring to the description of Albin and Pabonazo, we shall find that both pigments are classed together by Palomino as well as by Pacheco.
The purple tinge, observable in the colour of the Hæmatite, is to be attributed to the presence of a small portion of manganese, which is wanting in the ochres. The colour of the pigment, when washed and ground, is scarcely to be distinguished from Indian red.
The soft red Hæmatite is the mineral from which the Matita Rossa is prepared. This is proved by the following passage from Baldinucci’s Life of Cennini, (Opere vol. 4, p. 485). – “Among other things that I observed cursorily, Cennini, mentioning that stone with which we draw, and which we call ‘Matita,’ gives it the name of Lapis Amatito, agreeably to its true origin Lapis Hæmatitos, meaning stone of a blood colour.” The red chalk crayons, as they are called, now in use in England, are prepared by grinding Hæmatite to an impalpable powder in a porphyry mortar, and making the powder into pastiles with gum or isinglass (Mag. Science, vol. i. p. 349).
The Tierra Roxa of Palomino must have been different from the Pabonazo, since that author says its tint is deepened by time (en fortalecerse), whereas the Pabonazo did not change, (Pabonazo y Albin no hacen mudanza). It has been observed by many writers on colours, that ochres, whether raw or burnt, have a tendency to darken in time.
The red ore of iron, commonly called red chalk, or ruddle, is of a brick red, or brownish red colour, massive, and with an earthy fracture, is dull, soft, meagre to the touch, stains the fingers, writes easily, and adheres to the tongue. It is found in clay slate, in sand-stone and in lime-stone. Phill. Min. Tit. Red Iron Ore, – Sub Tit. Red Chalk.
Sinopia is often confounded with Armenian Bole; so it is translated by Dr. Holland the translator of Pliny. Geo. Agricola, who appears to have studied mineralogy so deeply, remarks that the colour of his Armenian Bole is “pallido,” whereas he says that of Sinopia is of the colour of liver, and when prepared is a pigment blood-red.
Cennino also appears to have well understood the difference between these minerals. He used the Sinopia in painting, but Armenian Bole in gilding.
Sinopia and Pabonazo, as we have observed, are ores of iron, but Bole is classed by Phillips (Min. p. 53.) among the clays; in the Treatise on Mineralogy, in the Encyc. Britann. it is placed in the Magnesian Genus. It is described as follows: –
Magnesian Genus, 2. Species Bole. Id. Kirw. I. 190. Le Bol, Broch. I. 459. Argile Ochreuse. Haüy. 445. – Exter. Char. Found massive and disseminated; surface dull, sometimes a little glimmering; fracture conchoidal, fragment sharp edged, colour yellowish brown or reddish, with spots and dentritical figures of black; opaque, rarely translucent at the edges; very soft; easily frangible; adheres to the tongue; feels greasy; streak shining; sp. grav. 1.4 to 2.
Chem. Char. Before the blow-pipe it becomes black or gray, and melts into a greenish gray slag. Falls to pieces in water with a crackling noise, and without forming a paste. Its constituent parts are stated by Bergman to consist of – Silica 47, Alumina 19, Magnesia 6.2, Lime 5.4, Oxide of Iron 5.4, Water 17=100.
The chief places which yield Bole, are the Islands of Lemnos, – hence called Lemnian earth—Sienna in Italy, and Strigan in Silesia, in which latter place it is deposited on indurated clay; in Upper Lusatia, it forms nests in Basalt. Bole and similar earths were formerly employed in medicine; they are now only used in the preparation of colours. – Encyc. Brit. Tit. Mineralogy.
I consider that it may be collected from the above extracts, that Sinopia is that species of Red Iron Ore called red ochre by Phillips and other mineralogists. This mineral will require the same preparation as a pigment as other earths; namely, careful washing and grinding.
BLUE COLOURS.
Palomino was right when he said that blue pigments were the Scylla of fresco painting. He had doubtless seen many instances of their want of durability and of their discordance with the other colours of the picture.
The remarks of Mr. Wilson and Mr. Hart, in the II. Report of the Commissioners on the Fine Arts, are a commentary on this passage. “The blue of the skies has either partially changed or entirely faded, whilst that of the drapery is comparatively well preserved. In the School of Athens he (Raphael) has painted the blues in fresco, and they have perished or nearly so, as they have, in most instances, in every part of Italy, where blue has been thus used; both in pictures of this and previous times. In the great works which Raphael subsequently painted in the Stanze, he returned to the old practice of painting the blues above red, probably dissatisfied with the crudeness which was the result of using them on the wet plaster. The blue that has thus been generally used seems to have been of a vegetable nature, as in many instances it has changed to a brilliant green. It may be urged that the use of ultramarine or cobalt, may obviate all necessity for such preparations, and secure the pictures against change; but whilst the former is by far too expensive a colour, the latter is crude and harsh in fresco. It seems to have been the blue which was used by the Carracci, and in their pictures, as in those of Guido, it will be found to be frequently out of harmony with the other colours; either these have in some degree faded, the blue remaining the same, or the blue has increased in intensity. Domenichino used distemper extensively in his works; but in those of Guercino will be found a triumphant solution of the difficulty; his blues are put in in fresco, and yet are in fine harmony with the other tones; they have generally a warm purple hue, and may be either smalt, or cobalt tempered with red, such as colcothar of vitriol. This is strongly exemplified in the Zampieri Palace at Bologna, where the harmony apparent in a fresco of Guercino is an agreeable relief, after the crudity which offends in those of his masters in other rooms of the same palace: a comparison between the Aurora of Guido in the Rospigliosi at Rome (all the blues of which are not retouched), and that by Guercino in the Ludovisi, further corroborates the above observations,” – Rep. 27. Again, Mr. Wilson observes, “The blue has come off entirely in some parts, and has evidently been laid on when the figures were finished, and the lime too dry, so that not being incorporated, it has come off in powder; in other parts where the artist has evidently been obliged to use it first, it is perfectly preserved.” Again, “The blues have been scraped off for the value of the ultramarine.” “The skies and water have faded to the usual blackish or slate colour.” “The nitre has almost entirely eaten up all the greens and blues.” “The blue backgrounds, on which the figures are relieved, are either turned black or purple, or have disappeared.” See II. Rep. pp. 36, 37, 42, 43, 44.
The “vivid blue,” in the church of St. Sigismond, at Cremona, and the blues in the pictures of Guercino, and the school of Carracci generally are almost the only exceptions to the general decay of the blue pigments in fresco. The colour is however more durable when applied in distemper.
It will be proper, in the first place, to enquire what blue pigments have been used, in painting on walls, by artists, and then to ascertain whether they can be employed with propriety in fresco.
The blue pigments mentioned by writers on art to have been used in painting on walls, are as follows: –
| PIGMENTS. | NAMES OF AUTHORS |
| Cæruleum or Vestorian Azure … | Pliny, Vitruvius. |
| Azzurro di Smalto … | Borghini. |
| Smaltino … | Pozzo, Orsini trans. of Vitruvius, Galliani, same. |
| Esmalte … | Pacheco, Palomino. |
| Smalto … | Lomazzo, Armenino. |
| Azzurro della Magna … | Cennino, Borghini, Benozzo Gozzoli, Books of the Duomo of Pisa. |
| Azzurro Oltramarino … | Lomazzo, Borghini, Vasari, Cennino, Pozzo, Palomino. |
| Azzurro di vena natural … | Malvasio, Borghini, Baldinucci. |
| Azul fino … | Palomino. |
| Azul di san Domingo … | Palomino. |
The preparation of the artificial pigment called Cæruleum, Vestorian Azure, and Vestorianum, is described by Vitruvius in the following terms:
“The composition of blue (Azzurro) was first discovered at Alexandria, and subsequently Vestorius established a factory of it at Puteoli. The manner of making it, and the ingredients of which it is composed, are rather remarkable. Sand is ground up so fine with flour of nitre, as almost to resemble wheat flour, and being mixed with copper filings, made with a coarse file like a rasp, the whole is sprinkled with water, that it may adhere together. It is then made into balls, by working it with the hands, and these balls are laid aside to dry. When dry, they are put into an earthen jar and the jar is put into the fire. And then, when the copper and the sand have united, boiling together by the vehemence of the fire, giving and receiving vapours from each other, they lose their own properties, and being united altogether by the force of the fire, they become of a blue colour.
“Similarly, on account of the scarcity of the colour Indigo, they make an imitation of that colour by mixing Selinusian or Anularian chalk, with the glass, which the Greeks call ὑαλον (hyalon).”
Sir Humphrey Davy observes,a “That this colour can be easily and cheaply made. I find that fifteen parts by weight of carbonate of soda, twenty parts of powdered opaque flint, and three parts of copper filings, strongly heated together for two hours, gave a substance of exactly the same tint, and nearly the same degree of fusibility, and which, when powdered, produced a fine deep blue.” The ingredients meant by Sir H. Davy, are nearly the same as those mentioned by Vitruvius, except that the latter mentions nitre, instead of carbonate of soda, and sand instead of flint, the difference in the latter, being merely nominal, since pure sand consists of silica almost in the state of powder, and flint also consists of silica in a consolidated form. Volumes have been written to ascertain what the nitre of the ancients really was, but the inquiry is unnecessary here. It is sufficient for our purpose to shew that the Vestorian Azure was a blue glass. I think I shall be able to prove that the blue pigment used in Italy and Spain during the latter half of the 16th century, and the whole of the 17th and 18th centuries, was of the same nature as this Vestorian Azure.
a On the Colours used by the Ancients. – Phil. Trans. 1815. See also Chaptal’s “La Chimie appliquée aux Arts.”
Bald. Orsini, the Translator of Vitruvius (Ed. of 1802), speaking of the Vestorianum, says, “this glass is synonymous with what the Italians call Smaltino, which was and still is used in fresco painting in Italy.” Orsini also remarks, (note to p. 96), “It is sufficiently clear that the Cæruleum of Vitruvius, is the same as Smaltino which is used in fresco painting, distempering it with milk, or with ox gall; that being mixed it may spread better because it is composed of a fine coloured glass. It must be spread with a brush over the intonaco before it hardens, and under it should be a coat of terre verte,a which serves for a ground (letto) for it. But Vitruvius says nothing respecting the manner of using it.”
a Mr. Wilson was informed by some Italian artists (See I. Rep. p. 27,) that a coat of Terra verte was laid at times as a preparation for blue, but I was told by Mr. Wilson himself that he had never found an instance of terra verte having been laid under blue.
The Marchese Galliani also, (trans. of Vitruv., edition of Naples), observes, in a note on this blue pigment of Vitruvius, “Blue in this passage does not mean the fine blue which is also called ultramarine, and which is made from Lapis Lazuli, ground to powder, but the other common sort of blue, which we call Smaltino.” Again, he says in another note on the “glass” mentioned by Vitruvius, “The blue colour made in this manner, is nearly the same as what is now used in fresco under the name of Smaltino.
Borghini remarks, (page 173), “There are many blue pigments, such as Azzurro di Smalto, which is made of glass, and is used in fresco.” He afterwards mentions Azzurro della Magna, thus proving that these pigments were not synonymous.
The only blue pigment mentioned by Armenino is Smalto; Lomazzo mentions Smalto, which he always distinguishes from the other azzurri amongst which he classes Ultramarine.
The Spanish painter Pacheco says, “Esmalte is the blue pigment best adapted for fresco painting, because it is glass,” &c. Palomino expresses himself nearly in the same terms with respect to this pigment; his words are, “The blue is the rock of this kind of painting; but fortune has not given us our choice in this matter, obliging us to use Esmalte, which is in substance ground glass.”
Pozzo mentions Smaltino as the blue pigment to be used in fresco. The directions for preparing various colours added to the Abecedario Pittorico (Naples, 1731), shew that Smaltino was prepared by mixing Zaffre with a salt instead of copper, and then of calcining the mixture.
It is impossible to decide whether the colouring material of the blue glass generally used in Italy was copper or Zaffre. The latter which is a mixture of cobalt with glass, now known by the name of Smalt,a was in use in Italy, where it was brought from Germany, before anything was known in the former country of its nature. Georgius Agricola, who was a German, does not mention it in his work, De Metallicis, published 1549. Neri (Arte Vitraia, p. 317-369, Florence, 1612), says its nature was unknown. It is probable that about this period smaltino made from Zaffre superseded that of which copper was the base. Lomazzo (Book iii, chap. 4) enumerating the pigments used in painting, says “Gli smalti, come quelle di Fiandra che è il migliore di gl’ altri tutti,” – “The smalti, such as that of Flanders, which is better than all the others.” From this passage we may infer that more than one sort of smalto was in use in Italy, and that one of these was of the same nature as the Vestorian Azure.
a The meaning of the word “Smalto” varies according to its use. It may mean enamel, mortar, cement, basis, ground, pavement, or floor; no conjecture therefore respecting its nature can be formed from its name.
This vitrified pigment, then, which is known by the various designations of Smalto, Azzurro di Smalto, Smaltino and Esmalte was used on the wet lime, and, according to the before-mentioned writers, the wetter the lime was when the colour was applied, the better. I shall now remind the readers of the general state of the blue colours in the Italian fresco paintings as described by Mr. Wilson and Mr. Hart, and then state my opinion that this pigment is the one that was generally employed in Italy and Spain for above two hundred years, and that it is quite unfit for the purpose, as is proved by the present state of the frescoes. I have not been able to discover when this colour was first introduced into modern painting, but I consider it probable that its introduction took place when the work of Vitruvius first began to be studied and translated in Italy.b It is to be observed that Vitruvius does not distinguish between such colours as were to be applied on the wet lime, and such as were to be used in secco (except in the case of lamp black, which he says was to be tempered with glue for painting on walls); but Pliny says decidedly (Book xxxv) of the Ceruleum, “Usus in creta; calcis impatiens,” – “It is useful on chalk, but is incompatible with lime.” He also includes this colour among those which cannot be used on a damp wall. The marginal note is as follows: – “Qui colores udo illini recusant,” – “Which colours cannot be laid on in fresco.” The text says, “Ex omnibus coloribus cretulam amant, udoque inlini recusant, Purpurissum, Indicum, Cæruleum, &c.” – “Out of all the colours, Purpurissum, Indicum, Cæruleum, &c. prefer chalk, and cannot be laid on in fresco.”
b The first edition of Vitruvius, without a date, appears to have been published about 1486. Two others were published in 1496 and 1497. (D’Agincourt, Architecture, p. 90, n.) The first Italian translation of Vitruvius by Cesariano was published in 1521, the second by Durantino in 1524, the third by Caporale in 1535, and the fourth by Barbaro in 1556. Perhaps this pigment was introduced during the life of Raphael, since Mr. Wilson mentions that he had painted the blues in fresco in the School of Athens, and that they had turned green, for we know that he, Michael Angelo, and other artists of that period were in the habit of laying on the blue in distemper. – (See Merimée de la Peinture à l’huile, p. 173.)
It is quite clear, therefore, that the Romans did not use it in fresco and the nature of the pigment proves it to have been unfit for this kind of painting. It was an artificial pigment, and it contained potash or soda, either of which would be a sufficient reason for refusing it a place among pigments to be used on lime.
It has been observed by Mr. Wilson and Mr. Hart, that “the blues and greens were eaten up with nitre.” Palomino also states that Luca Giordano retouched with the egg tempera those parts in which the nitre had appeared. Mr. Smith in his able paper on the Causes of and Means of Prevention of Saltpetre on the Surface of Walls, (II. Rep. p. 53-55.) observes that “salts will always make their way to the surface,” and that “lime, mortar, or some other sort of calcareous earth, seems to act as a vivifying principle to set the molecules of salt and water in action.” M. Durosiez also is of opinion that the presence of all alkalies in the substance of pictures is injurious, (III. Rep. 49). This then will be sufficient to account for the presence of nitre on the blue pigments in fresco paintings, where that pigment has been smaltino, and whether the colouring ingredient in that vitrified pigment be copper filings, or zaffre.
There is no doubt that it was the practice of the Greek or Byzantine school, and that of Giotto, and of the Italians generally, until after the death of Raphael, to add the blue pigments, in distemper, over a ground of black and red, or black only, or red only, or black and white.
Theophilus, who professes to teach all the Greeks knew respecting colours, in Chap. xv. of Book 1st of his Treatise on divers arts directs, that “on walls a coat of Veneda, that is, black mixed with lime, is to be laid as a ground; and upon this colour, when dry, must be laid, in the proper place, a thin coat of Ultramarine tempered with yolk of egg, mixed with plenty of water; and after this a thicker coat, to make it look well.” Cennino also directs both Ultramarine and Azzurro de la magna to be used to be tempered with egg, or glue. See Chap. 60, 72, 74, 83.
The blue commonly used by the early Florentine painters was called “Azzurro della Magna,” because it was brought from Germany, and sometimes “Azzurro” only. The colour used by Titian and the Venetians, was called by the latter name, and was brought to Venice from the East, as will be hereafter mentioned. I shall first give some early historical notices respecting these pigments, and shall then endeavour to ascertain their nature.
The following notice is extracted from the books of expenses incurred in the construction of the Duomo of Pisa.
“Anno 1392, de lib. M. Mag. Pierus, Pictor, de urbe veteri, habuit et recepit a d. operaris, pro una libra Azurri de la Magna, pro ystoria Ginesis de Campo Sancto, quod azurrum emptum fuit,” &c. – “In the year 1392, book M. Messer Piero, artist, of Civita Vecchia, had and received fron the Master of the Works, for one pound of Azzurro della magna, for the historical picture from Genesis, in the Campo Santo, which azure was bought, &c.”
The following extracts from letters written by Benozzo Gozzoli to Pietro de Medici, and preserved in the archives of the family of the Medici, throw much light on the manner of painting on walls at this period. He is speaking of the picture of the Three Magi, in the chapel of the Medici.a
a In the palace now called the Palazzo Riccardi at Florence. The chapel is now so built up that it can only be viewed by torch-light.
“I should have come to speak to you, but I have begun this morning to put on the blue (Azzurro) and I cannot leave it. The heat is great and the glue spoils directly. I think by next week I shall have completed this piece (Pontata). I think you would like to see it before I take down the scaffolding.” Dated Florence, 10th July, 1459. Again, “I remind you to send to Venice for the blue (Azzurro) because by this day week, this side (Facciata) will be completed and I want the blue for the other.” 11th Sept. 1459. “I had from the Jesuits two ounces of blue (Azzurro) of that kind which is three great florins per ounce.” 25th Sept. 1459.
Dr. Gaye, the editor of the “Carteggio inedito d’artisti dei secoli XIV. XV. XVI,” (from which these extracts are taken), Vol I. p. 193, observes, “the price of three great florins the ounce for Azzurro della Magna is much greater than has hitherto been considered the average price in the fifteenth century.”
From these extracts we learn the important fact, that the blue was applied in secco when the picture was nearly completed, and that it was mixed with glue.
Giovanni Liombani in a letter to Francesco Gonzaga, Marchese di Mantova, dated 22nd February, 1491, requests the Marchese “to cause a letter to be written to the respectable Zorzo Broguolo at Venice, ordering him to supply me with as much gold, silver, azurro, and other colours as shall amount to the sum of 200 ducats.” The artist, as appears from the same letter, was then going to paint in the palace in Marmirolo, of which no vestiges now remain.—See the same work. Vol. 1. p. 306.
It was the custom for the person who ordered the picture to supply the blue pigments as well as the gold. Even Titian observed this practice. He writes thus to the Doge of Venice, “Nor do I wish any other payment in advance than colours to the value of 10 ducats and 3oz. of that Azzurro, if there be any, in the Offitio del Sal,” &c. By a decree dated the 28th January, 1515, the Council order, among other particulars, “that Titian shall have only colours to the amount of 10 ducats and 3oz. of Azzurro.”
Modern writers have supposed that Azzurro della Magna was cobalt blue; but I apprehend without sufficient reason. The principal reason seems to be, that both pigments were produced in Germany. Georgius Agricola does not appear to have been aware that cobalt could be used as a pigment; he describes (p. 466) three kinds, differing principally in colour; the first was black, the second grey, and the third the colour of iron. He says that cobalt corrodes and consumes the hands and feet of those who work it, if they are not careful to defend themselves from it. Matthioli, (Comm. on Diosc. p. 1395) observes, that “Kobolt is a corrosive substance, that frequently ulcerates the hands and feet of those who dig it, nor is this to be wondered at, since it kills like deadly poison.” He adds, that in Bohemia it is used to kill flies, but he says nothing of its being used as a pigment. The art of purifying and preparing cobalt as a pigment, is of comparatively modern invention, at least in Europe, and it is extremely probable, indeed almost certain, that it was used in the form of Zaffre as a pigment, long before the art of preparing a pigment of a pure blue colour from it was known; Zaffre not being a pure blue, but inclining to red. It appears also, that the process described by Cennino (chap. 60) for preparing Azzurro della Magna for use, is not applicable to the mineral cobalt, which requires chemical preparation before it can be used as a pigment; for we have seen that the natural colours of this mineral are black, grey, and the colour of iron, and not blue. The simple process of grinding and washing it with water, would not be sufficient to develope the blue colour of cobalt; if it were, it is quite clear, the long and troublesome processes, now in use for purifying this mineral, are unnecessary; besides, if cobalt required chemical preparation, it could scarcely be included with propriety in Cennino’s list of natural pigments. (See Cenn. chap. 60, and for the modern method of purifying cobalt, see Ure’s Dict. of Chemistry and Mineralogy, Chaptal’s Chimie appliquée aux Arts, M. de Brongniart’s Traité des Arts Céramiques, Merimée, De la peinture à l’huile, Marcucci Saggio Analitico dei Colori, &c.)
The ancients possessed some native blue and green pigments, to which they gave the names of Chrysocola, Lapis Armenus, Cæruleum, and Cyaneum, (see Pliny, Lib. xxxv. Chap. 6). The first is green, the second greenish-blue or blue, the third and fourth blue. Geo. Agricola, Matthioli, and Laguna, mention pigments of the same name. All agree in the general description, but vary in their account of the colour. They also agree in stating that they were found in copper and silver mines, and sometimes in gold mines, frequently close together, and even adhering to the same piece of ore, and that they were a certain criterion of the presence of copper. The fact is, that they were all native carbonates of copper, changing their name according to the prevalence of the blue, or green, or greenish-blue colour. The first (Chrysocola) will again be noticed. The Armenian Stone is by most writers described to be of a greenish blue colour, and this corresponds, as I shall prove, with the Azul Verde of Palomino, and the Verde Azzurro of the Italians. The Cerulea is the native blue carbonate of copper, of which there are two species, the earthy and the indurated; the last was frequently mistaken for the Lapis Lazuli, from which ultramarine is prepared.
I shall give, concisely, Agricola’s description of the pigment he calls Cæruleo. He says, (p. 219, 221) there were two kinds known in his time, the native and the artificial; that the native was often attached to the same ores as Chrysocola, namely, copper ores; that it was found not only in copper mines, but in those of silver and gold, and that it always shewed the presence of copper; that it was brought from Spain, Germany, Noricum, Dacia, Rhætia, &c., but was scarce because the factitious was more in use. He adds (p. 452), “now this is the Ceruleo which the vulgar call azzurro, which, together with the Chrysocola, is attached to the ore,” (or matrix). He says also, that it resembled a hard sand, and is scraped off the ore like sand. And see also Matthioli (p. 1412), who agrees in the general description. The mineral here described is clearly the earthy blue carbonate of copper, of which the following description is given in the Encyc. Brit. Art. Mineralogy.
SUBSPECIES I. EARTHY AZURE COPPER ORE. – Exter. Char. Rarely found massive, usually disseminated or superficial; composed of fine particles, which are dull and somewhat coherent; fracture earthy.
Colour, smalt blue, sometimes sky blue; opaque; stains a little; soft or friable.
The earthy variety is found in superficial layers on a slaty marl in Hessia, and it is also found superficial on sandstone in Thuringia. Sometimes the whole of the sandstone is impregnated with this earthy carbonate of copper, there called copper sand earth or copper sand stone. A similar sand stone, at Gourock near Greenock, in Scotland, was, a few years ago, dug out for the purpose of extracting copper. – (Enc. Brit. Art. Mineralogy.)
The resemblance between this species, and the mineral described by Agricola, is obvious. The indurated species is rare. Azure copper ore is found in veins of primitive and secondary mountains, chiefly with the green carbonate of copper and red oxide of copper, in Chili, Bohemia, the Hartz, Saxony, the Uralian mountains, and in Thuringia, at Chessy in France, &c.
In Cornwall, sparingly in Huel Muttrell and Huel Gorland, Huel Unity, Huel Virgin and Carbarack. In the Buckingham mine, near Bridgewater, Somersetshire. At Alderley Edge, in Cheshire, in sandstone with yellow copper and barytes. In Durham, at Wassing-hope lead mine near Stanhope, in small nodules imbedded in sulphate of barytes. In Scotland, at Wanlock Head, and the lead hills in Lanarkshire. (Phillips’ Mineralogy, p. 310). Phillips classes this mineral under the head “Native Metal and Metalliferous Minerals.”
Modern writers on the composition of colours, call this pigment Bleu de Montagne—Mountain Blue – Blue ochre of copper. – Lomazzo mentions the colour under the name Ongaro.a
a Because it was brought from Kerhausen in Hungary. Marcucci (p. 70) enumerates it among the green pigments, a circumstance which identifies it with the Lapis Armenus which was sometimes blue and sometimes green.
With regard to the last appellation, Ongaro, Pacheco (p. 373) relates a circumstance not generally known. “Philip, Count of Flanders, ordered Michael Coxis of Malines to make a copy for him, of the celebrated picture by Van Eyck at Ghent; he copied it extremely well, and because they could not procure any azure so fine as that used in the original, they sent to Titian, who was at Venice, for some of a natural azure, which is found in Hungary, which was formerly very easy to procure, before the Turks were masters of that province, and the blue for the drapery of the figure cost thirty ducats.” Perhaps this was some of the same kind of azure that Titian desired the Doge to send him (if there were any). This anecdote shews, that the blue carbonate of copper was used in oil by Titian, and probably by Van Eyck, since no other blue could be found in Flanders which matched that in the picture.
Much confusion has been occasioned by some authors describing the Lapis Armenus as a blue stone, while others say it is green. The fact is, that it consists of one of those ores of copper united with other substances, and that it is sometimes blue, sometimes green, and sometimes of a greenish blue. See Pliny, Book xxxv. c. 6. G. Agricola, De Metallicis, 219, 221, 452. Constant de Massoul’s Treatise on Painting, and the Composition of Colours, 152, and Bulengerius de Pictura, Sculptura, et Plastice, Lib. ii. c. iii. Le Vieil (De la Peinture sur Verre, p. 108, n.) says, it is a stone of a lighter colour, not so heavy and more friable than ultramarine; it is found in France, Germany, and especially in the Tyrol. G. Agricola (p. 452) mentions, that “he saw some Armenio in one shop only in Venice, and that the possessor valued it much.” The scarcity of the pigment is sufficiently accounted for, by the provinces which produced it being in the hands of the Turks. The Venetians, however, seem to have maintained an intercourse with them, since Gentile Bellini was sent to practise his art, at the court of Mahomet the Second, at Constantinople. As merchandize is generally imported in considerable quantities, the Armenio seen by Agricola at Venice, in one shop, might have been the remains of the old stock imported while the Turks and Venetians had still commercial relations. It is not the blue pigments only which became scarce on account of the wars, the Sinopia also fell into disuse about the same period, as Agricola declares, and from the same cause. Another reason also for the scarcity of the carbonates of copper was, as we have before observed, the use of the artificial pigments prepared in imitation of the natural pigments; many recipes for which are to be found in every work on colours.
Matthioli (p. 1412) observes, “Armenian stone is of a bluish colour, although not a pure blue, nor is it so hard as the stone called “Azulo,” because the Armenian stone is of a sandy nature, and the painters sometimes use it instead of Azzurro.” He says also that the same mineral was found in Germany as well as in Armenia, and he adds that the Armenian stone which the painters use, being taken in the quantity of the twelfth part of a drachm, was useful in removing melancholy. It was also given to children for disorders of the breast, &c. This is sufficient proof that the Armenian Stone was not Cobalt, the poisonous nature of which was well known to Matthioli. In another place (p. 1415, line 58) he gives the name of Verde Azzurro to the Armenian Stone, which sufficiently identifies these minerals. Laguna, the Spanish commentator on Dioscorides, is still more precise, he says, “This kind of stone resembles much in its colour Chrysocola, and that is considered the best which is green with a mixture of blue. From whence I am persuaded that the common stone which is found in so many mines, of which the perfect colour Verde Azul is made, is a species of the Armenian Stone.” – p. 539. See, also, Dr. Holland’s Translation of Pliny, p. 531, where he calls this pigment Verd’ Azzur.
Matthioli observes (p. 1413) that the Arabs confuse the Pietra Cerulea, by which he means Lapis Lazuli, with the Armenian Stone; indeed the resemblance between all these minerals is so great, that they can scarcely be distinguished by inspection. I have a specimen of ore which one mineralogist pronounced to be the Blue Carbonate of Copper, while another to whom it was shewn called it Lapis Lazuli. The only apparent difference between the indurated Blue Carbonate of Copper and Lapis Lazuli appears to be the presence or absence of the spots or veins of gold which are always found in the finest coloured specimens. The Lapis Lazuli may be distinguished from the Carbonate of Copper by subjecting it to the action of fire. The former will be unchanged, but the latter turns black. – See Massoul, pp. 166, 176. Let us hear what Matthioli, speaking of the stone to be used as a medicine, says of the Pietra Cerulea, “It is true that that stone which sparkles with gold should be used; because the others with which the apothecaries, and those who prepare Azzurri in Germany are always provided, are not nearly so beneficial.” He also says, “he has seen great quantities of Armenio and Ceruleo in silver mines, in a great many places in Germany, but he never found any which was veined with gold.” Cennino (chap. 60) mentions Azzurro della Magna in nearly the same terms. Matthioli continues, “That which is called Ultramarine, and which is made of the true Lapis Lazuli from gold mines, is in great esteem, because it surpasses in goodness and in colour all the Azzurri in the world.” The Ceruleo was probably the indurated blue carbonate of copper, which much resembles the Lapis Lazuli. – See Massoul’s Art of Painting, p. 176. Laguna adds that Matthioli was satisfied that the stone called Armenio, was of the same nature as the Cerulea or Cyano (Lapis Lazuli), but that the former was not perfectly formed in the mineral veins; “and in truth we must believe implicitly all he tells us, for he was a most acute and accurate investigator of the nature of all minerals.” We may add that the true Lapis Lazuli is not produced in Europe but is brought from Asia, especially from Persia, where it must have been once in great abundance, since we learn from the book of Esther, c. i. v. 6, that the pavement of the palace of Ahasuerus consisted “of red, and blue, and white, and black marble.” For the description of Lapis Lazuli, see Phillips, Jameson, Ure, Encyc. Brit. Art. Mineralogy, Tit. Lazulite.
I trust I have now proved satisfactorily that the pigments called Azzurro, Azzurro della Magna, Ongaro, and Verde Azzurro were native blue carbonates of copper, and that the latter was the Armenian Stone of Pliny, of Agricola, and of Matthioli. I shall now endeavour to prove that they were also called “Azzurri di Spagna,” and “Azzurri di Vena Naturale.”
Malvasia mentions (Fels. Pitt. vol. ii. p. 349) that he discovered in the studio of Cesare Baglione, many years after his decease, “a chest full of brushes and colours, that is, earths of all sorts, particularly of verde di miniera, the most precious which the ancients possessed, the good and genuine sort of which is now lost. Also some fine Verdetto, and some Azzurri di Spagna, so bright and fine that even Sirani was deceived by them, and at first mistook them for ultramarine.” The reference to this passage in the index is as follows: – “Azzurri e verdetti di Spagna cosi belli anticamente per i frescanti oggi perdutisi, nè più in uso,” – “Spanish blues and greens, anciently so fine for fresco painters, now lost and no longer in use.” Malvasia says “now lost,” we must first endeavour to ascertain when they were lost; Sirani, he adds, was deceived by them; now Sirani died in 1670.
These colours were lost, therefore, previous to 1670, and probably some time previous, as Sirani did not appear to know them. Cesare Baglione died in 1590, having the colours in his possession; they were therefore in use in 1590, and must have been lost at some period between 1590 and 1670.
Guercino painted in Bologna in 1618, in the Zampieri Palace in 1631, in the Ludovisi at Rome in 1621, (See Malv. vol. ii. p. 363, 365, 368). Mr. Wilson observes, that the blues in his pictures, at these places, are put in in fresco, and are yet in fine harmony with the other tones. Is it not possible he may have used the Azzurri di Spagna?
If, then, this Azzurro di Spagna is so good a colour, it may be asked, why do not the Spanish writers mention it? Palomino, it is true, does not mention the colour, but he does mention a blue stone called “Ignoto” (unknown), which was sometimes used with other blues in fresco, and which is very likely to have been the pigment in question. To account for Palomino’s being unacquainted with so valuable a pigment, a production of his native country, we must remember that the Spaniards received the art of fresco painting from the Italians, and adopted their method, and that Palomino died in 1726, fifty-six years at least after we have ascertained the pigment to have been lost. Pacheco’s Treatise was published in 1641; he also does not mention the colour; it was therefore unknown or disused in his time in Spain and Rome, for he resided some time at Rome.
Borghini mentions (Riposo, p. 173, published 1585), that “Azzurro di Vena Naturale was useful in all three kinds of painting.” Baldinucci observes of the same pigment, that “it was used in painting in fresco, in oil, and in distemper.” These extracts prove that the pigment had been used in Italy in fresco painting, although it is not mentioned by many writers on this subject.
I have proved from Agricola that the mineral which the vulgar call “Azzurro” was produced in Spain in copper and silver mines, and I have shewn that the mineral could not be cobalt, because in its natural state that mineral is not blue. We know the pigment mentioned by Malvasia was not Ultramarine, because that substance is not found in Spain, and because he says the Azzurri di Spagna were lost, whereas Ultramarine was then in use in Italy. We can, therefore, form no other conclusion but that these pigments are native blue carbonates of copper, and of the same nature as Azzurro della Magna, Ceruleo, Mountain Blue, Ongaro, &c.
With regard to the use of Ultramarine in fresco, it appears that this was one of the expensive colours, which were always supplied by the owner of the picture. Pacheco says that in his time it was not used in Spain because it was so scarce and dear; but we find from Laguna’s Commentary on Dioscorides (p. 538) that it had been used in Spain prior to 1570, and that its colour was thought so fine that it was used to paint the royal chapels. Palomino, however, gives another reason why it was not used in fresco, namely, “that the lime so acts upon it, that it fades, and after a short time the lights cannot be distinguished from the darks.” He directs that for interiors, the Ultramarine is to be laid on in secco, with goat’s milk. I have found repeated instances mentioned of the use of Ultramarine in secco on fresco paintings, but not one of its use in buon-fresco. Palomino mentions yet another pigment used in secco on walls, namely, Azul fino, or Azul de Santo Domingo, which appears to have been an artificial pigment made from copper, probably synonymous with the Azurri di Biadetti of Borghini, and the modern “cendres bleues.” But it is unnecessary to describe artificial pigments in this place.
French Ultramarine has also been tried in fresco, but I understand from high authority is not approved. Indigo was used occasionally in fresco by Cennino and Palomino, the latter, however, observes, “this colour should never be laid on the lime itself, as it always perishes.” Pozzo says, it could be used in fresco during the summer, but not in winter, because it is a bad drier.
To conclude, it is well ascertained that the brothers Campi of Cremona, Bernardino Gatti (Il Sogaro), and Guercino (I. Rep. pp. 27, 40) possessed a blue pigment, which has proved permanent in fresco painting. It appears also that a blue pigment was used in Italy which was lost sometime between 1590 and 1670, and that from the date of Guercino’s paintings, it is very probable that he used it, that this pigment was called Azzurro de Vena Naturale, which there is strong reason for supposing to be native blue carbonate of copper.
With regard to this mineral itself it is a natural production said to consist of carbonate of copper, alumina, and lime,a and is, I believe, produced in sufficient quantities for use as a pigment in fresco.
a According to Pelletier it is composed of oxide of copper 50 parts, carbonic acid 30, oxygen 10, lime 7, water 3, = 100.
It would be desirable to ascertain, by analysis of the blue colours on pictures, what blue pigments have been used in fresco in Italy, in order to select for future use such as have been found durable, and to avoid such as have perished.
The method of preparing the carbonates of copper for use as pigments, is by the simple process mentioned by Cennino, (chap. 60), namely, grinding and washing it, in order to separate the small stones that are sometimes mixed with it. – See Massoul’s Treatise on Painting and the Composition of Colours, p. 176. Marcucci Saggio Analitico, &c., p. 70.
GREEN COLOURS.
The employment of green colours in fresco is attended with less difficulty than the blue. This arises from several causes, not altogether depending on the pigment used. I allude in the first place to the mixture of blue pigments with yellow ochres, and to the tendency of blues to become green.
The green pigments used in fresco are terra verde (the nature of which is too well known to require any description) Verde Montaña, Mountain Green, Lapis Armenus, the Chrysocolla of the ancients, a native green pigment supposed to be a mixture of oxide of copper, or, as some say, carbonate of copper with alumina and lime. This mineral is of an emerald green or verdigris green colour, and sometimes a sky blue. – See Phillips’ Min. p. 309, 313. – Encyc. Brit. p. 228, 289. – G. Agricola de Metal. p. 219, 221.
Andres de Laguna (Translation of Dioscorides, Salamanca, 1570), observes, the use of the mineral or native chrysocolla was very common centuries ago, for painting the apartments of the superb palaces of princes, on account of its beautiful green colour, which is so agreeable to the eyes. The greenest, and the pleasantest to the sight is that which is found in the mines of copper.
Another species of copper ore, called Earthy ferruginous green copper ore, which is of a light olive green colour, seems to have been used in Spain under the name Verdacho, which Pacheco says agreed better with the lime than Verde Montaña.
A third species of copper ore, the Malachite, is also used in painting. – See Merimée, De la Peinture á l’huile p. 187. De Massoul sur l’art de la Peinture, p. 151, 152.
Verde Granillo is the best sort of Verde Montaña, it was brought from Venice to Spain in pastilles.—Italian writers call Verde Montaña, Verdetto and Verde de Miniera. This pigment must not however be confounded with the verdete of the Spaniards which is verdegris.
Palomino says that Verde Montaña should not be used alone on the lime, but that it should be mixed with terra verde, when its colour will be beautiful and durable.
Marcucci directs (p. 71), that the mineral should be ground and made up into small cones. This was the process adopted in Venice, where the pigment was called “Verde Granillo.”
Pozzo includes a vegetable green pigment in the list of colours for painting in fresco. The adoption of this colour cannot be recommended.
Mr. Hart observes (II. Rep. p. 43), that the greens in certain frescoes are well preserved; in the Ducal Palace of Mantua, however, he says that they are almost entirely eaten up with nitre.
Now imitations of the native green and blue carbonates of copper have been in use from the earliest times as we learn from Pliny, also from Theophilus and other writers of the middle ages, as well as from G. Agricola and Matthioli, and the more recent Italian and Spanish authors. The use therefore of these pigments in fresco, would be sufficient to account for the appearance of nitre upon the green and blue parts of such paintings. We know from Malvasia’s Felsina Pittrice that these native green pigments were lost in Italy previous to 1670.
Lomazzo observes (Trattato p. 194.) that Perino del Vaga invented a colour formed of Verdetto, and bianco secco, that is, lime-white in powder, which he (Lomazzo) remarks had a beautiful effect in fresco, and produced a colour almost resembling Giallorino. Of course, as Lomazzo spoke of a contemporary, he could give no opinion as to the durability of the pigment.
BLACK COLOURS.
Black colours are among those that have been found least durable in fresco. – See II. Rep. p. 42. All writers are unanimous in saying, that none but natural pigments should be used in fresco; therefore carbonaceous blacks, prepared from animal and vegetable substances, should be excluded from this kind of painting.
Native black colours are fortunately abundant. The Terra Nera de Venezia, of which Pozzo speaks, is said by Palomino to be a most beautiful colour in every respect. There is also Terra Nera di Roma, Terra Nera di Piedemonte, the mineral called black chalk (schiste à dessiner, ampelite graphique), which is met with in France, Spain, Italy, Iceland, Wales, Ireland, and the Hebrides, and which is used both in drawing and painting.
Nero di schiuma di ferro, mentioned by Borghini, is an artificial pigment, prepared by mixing the scales from red hot iron with terra verde, and then grinding the mixture to a very fine powder, (Baldinucci, Voc. Dis. Borghini). Neither this nor the next can be recommended.
Nero di Terra di Campane, mentioned by Armenino, is prepared from a sort of crust which forms on the moulds in which bells and cannons are cast. It was used in fresco painting, but Baldinucci says, that when exposed to the air, in a short time the colour flies, and spoils the picture.
These black earths are especially useful in making true greys; the extreme darks, every one knows, should be formed of browns, and not of blacks. It is well observed, by the author of an article in the Quarterly Review for December, 1844, entitled “Painting in the 14th Century,” that “pure black should never be admitted on walls or canvass, for the simple reason that it hardly exists in any department of nature which can come within the sphere of imitation.”
WHITE, YELLOW, AND BROWN COLOURS.
THE only white pigment that it is necessary to mention here is Bianco Sangiovanni; the others are all fully described by the several authors whose works are translated, and form part of this treatise. Cennino Cennini has left the following directions for preparing Bianco Sangiovanni: –
“Take very white slaked lime; pulverise it, and put it into a little tub for the space of eight days, changing the water every day, and mixing the lime and water well together in order to extract from it all unctuous properties. Then make it into small cakes, put them upon the roof of the house in the sun, and the older these cakes are, the whiter they become. If you wish to hasten the process, and have the white very good, when the cakes are dry, grind them on your slab with water, and then make them again into cakes, and dry them as before. Do this twice, and you will see how perfectly white they will become. This white must be ground thoroughly with water. It is good for working in fresco, that is, on walls, without tempera; and without this colour you can do nothing,—I mean, you cannot paint flesh, or make tints of the other colours which are necessary in painting on walls, namely, in fresco; and it never requires any tempera.” – Cennino, p. 31.
The yellow colours, consisting of ochres of various shades, require no particular notice. Giallorino (Naples yellow) is however sometimes admitted into fresco painting, but it should not be used where the paintings are much exposed to the air.
The brown colours are also too well known to need a separate notice. The artist will, of course, remember the tendency of umber to grow darker with time, and will avoid those pigments which contain vegetable matter.
CONCLUDING REMARKS.
Having thus inquired into the nature of the various colours used in fresco painting, I may be allowed to observe in conclusion that all writers are agreed in certain general principles, namely, that none but natural earthy colours can be used with safety and propriety in fresco painting, that these colours are not brilliant, but rather the contrary, and that they derive their beauty from the harmony of the arrangement, and the judicious opposition of the colours. Cennino and others praise certain colours which they say are equal to lake in fresco; they are right, because the colours to which they allude will appear like lake when skilfully contrasted with the other colours used in this kind of painting, but if compared with the colours we call lake and carmine, I have no doubt they would be found very dissimilar. The Amatito and burnt Roman vitriol will harmonize well with the ochres and other earths, but if lake were used, (supposing it could be used in fresco), it would, like the bright blue in the frescoes of Romanelli in the Louvre, and those of the Carracci, be out of harmony with the rest of the picture. If lakes and cobalt be used in fresco, it will be necessary to procure yellows of equal brilliancy, but I apprehend that pictures painted with such colours would lose in harmony what they gained in brilliancy; such colours are too glaring and intrusive for the decorations of buildings. To judge of their effect it is only necessary to compare the ceilings of the Louvre painted by the modern French school, which are as brilliant as the finest lakes, yellows, and blues can make them, with the quiet beauty and mellowness of the frescoes of Romanelli in the Salles des Antiques, (always, however, excepting the blue, which is too powerful for the other colours). It will be remembered that Titian and Raffaello used chiefly earths and common colours even in painting in oil, instead of the more expensive and brilliant colours. No one capable of forming an opinion can suppose they would have preferred the former to the latter, if they had not had the best and most convincing reasons for so doing. We are all too much inclined to seek the perfection of colouring in the pigments themselves instead of in the harmonious combination and opposition of the several colours, and to attribute to the vehicle and colours the effect which the skill of the artist alone can produce.
There is one point, however, on which particular care is required, namely, that the colours used should be the very best of the kind, the brightest, purest, and finest that can be obtained, and besides that, it is necessary, as Armenino observes, to be very clean and careful in using them in order to preserve them pure and distinct, because, by every slight mixture that falls into them, they become soiled and lose a great deal of their brightness.
In conclusion, I may observe that considerable difficulty and much labour has been added to this investigation, arising from the confusion in the names and technical terms, some authors using the names derived from the Greek, others from the Latin, others from the Arabic, and others the names derived from the colloquial language of commerce. In the same language, different terms are used, and different names given to the same substances; and not unfrequently, the same names are given to different substances. It will also be considered that the investigation has been pursued through various languages, written at periods distant from each other, and by authors, some with an extensive, others with a limited knowledge of the subject. These circumstances have added to the difficulties of this inquiry, and with the candid reader will form some excuse for any mistakes that may have occurred in this investigation.