Coal-tar Colours
: ON THE PRIMARY, RED.Our work might be considered incomplete without some allusion to the
coal-tar colours, even though they are rather dyes than pigments, not
possessing sufficient stability for the palette. To avoid repeated
reference, we have preferred grouping them in this chapter, irrespective
of hue. Consequently, yellow, red, blue, orange, green, purple, brown,
and black, will be all comprised under the heading of coal-tar colours.
Previous to the year 1856 the colouring matters derived from coal-tar
were practically unknown. Until then, that black evil-smelling substance
was looked upon as almost worthless; but gradually the unsightly grub
emerged into a beautiful butterfly, clothed first in mauve and next in
magenta. After its long winter of neglect, there sprung from coal-tar
the most vivid and varied hues, like flowers from the earth at spring.
At a touch of the fairy wand of science, the waste land became a garden
of tropic tints, and colour succeeded colour, until the whole gamut had
been gone through. Never was transformation more dazzling or more
complete. The once despised refuse was now a valued commercial
product--indeed a trade in itself. Perfectly fascinated by the study,
chemists threw themselves heart and soul into coal-tar, and coal-tar
colours were to be seen everywhere.
It were beside our purpose to enter into the various stages through
which coal has to pass to become colour. Enough to state that to the
introduction of gas-light we are indebted for the acquisition of
coal-tar colours, the starting point for the production of mauve,
magenta, &c., being the manufacture of coal-gas. From the destructive
distillation of coal, coal-tar oil results; and from this are obtained
the products which yield the colours in question. Among these products
may be mentioned aniline, rosaniline, napthaline, chinoline, carbolic
acid, picric acid, &c., with their derivatives.
Of the fifty-one compounds furnished by the distillation of coal,
perhaps the most popularly associated with coal-tar colours is aniline,
to which we will therefore confine ourselves. Discovered in 1826, this
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I Have Fully Tested The Qualifications Of Aureolin For The
Landscape Painter, and, without hesitation, pronounce it to be the most valuable addition to the 'colour box' since the introduction of Rose Madder. It has supplied a deficiency of a very important character. Hitherto, no Primitive Yel... Real And Lasting Benefit To Pictorial Art In General The
permanence and unaltered purity of its lightest and faintest tints we are assured may be confidently relied upon, inasmuch as they have been fully established by the most severe tests to which colour can be subjected, by several of our... Will Not Only Be Regarded By The Artist As A Great Boon In The
production of his works, but it must also be considered as a ... Arsenic Yellow
... Cadmium Yellow {cadmium Carbonate Of Cadmium (white)
{Sulphur. / \ / \ / \ / \ / \ / ... Chrome Browns
are produced by various methods of several hues, tints, and shades, both by wet and dry processes. We have obtained them by many methods, of different degrees of permanence. Some very intense in colour have stood well, while others paler and more de... Elsner's Green
is also a combination of tin and copper. It is made by adding to a solution of sulphate of copper a decoction of fustic, previously clarified by a solution of gelatine. To this mixture are added ten or eleven per cent. of protochloride of tin, and l... Anotta
Annotto, Annatto, Arnotto, Arnotta, Terra Orellana, Rocou, &c., is met with in commerce under the names of cake anotta, and flag or roll anotta. The former, which comes almost exclusively from Cayenne, should be of a bright yellow colour: the latter... Antimony Orange
Golden Sulphur of Antimony, or Golden Yellow, is a hydro-sulphuret of antimony of an orange colour, which is destroyed by the action of strong light. It is a bad dryer in oil, injurious to many pigments, and in no respect eligible either in water or... Antimony Red
Or Mineral Kermes. We have obtained this colour ranging from light orange to deep carmine, of different degrees of brightness and stability. Some of the tints stood well in a book, but faded on exposure to light and air; and some even vanished when ... Archil Purple
Archil may be regarded as the English, cudbear as the Scotch, and litmus as the Dutch name for one and the same substance, extracted from several species of lichens by various processes. These lichens, which are principally collected on rocks adjace... Bismuth Purple
A purple powder is capable of being produced from bismuth by passing chlorine gas through the hydrated oxide suspended in a saturated solution of potash. As soon as the oxide becomes brown-red, the mixture is boiled and the liquid decanted off at on... Bismuth Yellow
Or chromate of bismuth, may be obtained either as a lemon or an orange yellow, sparingly soluble in water. The colour is not permanent, and turns greenish-brown even when excluded from light and air. ... Black Chalk
is an indurated clay, of the texture of white chalk, and chiefly used for cutting into crayons. Fine specimens have been found near Bantry in Ireland, and in Wales, but the Italian has the most reputation. Crayons for sketching and drawing are also ... Black Ochre
Earth Black, or Prussian Black, is a native earth, combined with iron and alluvial clay. It is found in most countries, and should be washed and exposed to the atmosphere before being employed. Sea-coal, and other black mineral substances, have been... Blue Ashes Or Mountain Blue
are both hydrated carbonates of copper, the first being artificially prepared, and the second found native in Cumberland. Neither is durable, especially in oil; and, as pigments, both are precisely of the character of verditer. By treating the natur... Blue Carmine
In a former edition of this work there appeared the following:--"Blue carmine is a blue oxide of molybdenum, of which little is known as a substance or as a pigment. It is said to be of a beautiful blue colour, and durable in a strong light, but is ... Blue Ochre
which has been improperly called Native Prussian Blue, is a native hydrated phosphate of iron of rare occurrence, found with iron pyrites in Cornwall, and also in North America. What Indian red is to the colour red, and Oxford ochre to yellow, this ... Blue Verditer
or Verditer, is an oxide of copper, formed by precipitating nitrate of copper with lime. It is of a beautiful light blue colour, little affected by light, but greened and ultimately blackened by time, damp, and impure air--changes which ensue even m... Bone Black
obtained by charring, is similar to that of ivory, except that it is a little warmer in tone, having a reddish or orange tinge, and is a worse drier in oil. Like ivory black, it is very transparent. Immense quantities of bone black are consumed with... Burnt Madder
is obtained by carefully charring madder carmine until it becomes of the hue required. Bearing the same relation to madder carmine as burnt carmine to the carmine of cochineal, burnt madder is a permanent and perfectly unexceptionable pigment. By re... Burnt Verdigris
is what its name expresses, and is an olive-coloured oxide of copper deprived of acid. It dries remarkably well in oil, is more durable than the original verdigris, and is in other respects an improved and more eligible pigment, although not to be r... Cadmium Brown
By igniting the white carbonate of cadmium, among other methods, a cinnamon-brown oxide is obtainable, of a very clear and beautiful colour if the process be well conducted. It is, however, not eligible as a pigment, owing to the rapidity with which... Cadmium White
Provided the metal be freed from iron, which we have commonly found to be more or less present, a white of considerable beauty may be produced; either directly by precipitation as hydrated oxide or carbonate, or indirectly by exposing the brown anhy... Cassia Fistula
is a native vegetal pigment, though it is more commonly employed as a medicinal drug. It is brought from the East and West Indies in a sort of cane, in which it is naturally produced. As a pigment it is deep, transparent, of an imperfect citrine col... Catechu Browns
... Chica Marrone
Chica, the red colouring principle alluded to in the ninth chapter, is ... Chica Red
Is extracted from the leaves of a tree growing in central and southern America. A sample examined by Mr. O'Neill was in small irregular lumps, of a bright scarlet colour, adherent to the tongue like indigo, and taking a metallic polish of a greenish... Chocolate Lead
or Marrone Red, is a pigment prepared by calcining oxide of lead with about a third of copper oxide, and reducing the compound to a uniform tint by levigation. It is of a chocolate hue, strong opaque body, and dries freely. Like all lead and copper ... Chromate Of Mercury
has been improperly classed as a red with vermilion, for though it is of a bright ochrous red in powder, when ground it becomes a bright ochre-orange, and affords with white very pure orange tints. Nevertheless it is a bad pigment, since light soon ... Chrome Arseniate
is an agreeable apple-green colour, prepared from arseniate of potash and salts of chromic oxide. It is durable, but possesses no advantages over the chrome oxides, and is of course poisonous. ... Citrine Brown
From boiling, hot, or cold solutions of bichromate of potash and hyposulphite of soda in excess, we have obtained an agreeable citrine-brown colour, varying in hue and tint according to the mode of preparation and proportions of materials employed. ... Coal-tar Colours
Our work might be considered incomplete without some allusion to the coal-tar colours, even though they are rather dyes than pigments, not possessing sufficient stability for the palette. To avoid repeated reference, we have preferred grouping them ... Cobalt Green
Rinman's Green, Vert de Zinc or Zinc Green. True cobalt green is made by igniting a very large quantity of carbonate of zinc with a very small quantity of carbonate of cobalt. To give a green tint to an enormous proportion of the former, an inapprec... Cobalt Marrone
There is obtainable from cobalt a very rich marrone brown, which, like many other colours, is more beautiful while moist than when dried. Permanent, if carefully made and most thoroughly washed, it is an expensive compound, and must rank among those... Cobalt Prussian Blue
Gmelin states that yellow prussiate of potash yields with a solution of oxalate of sesquioxide of cobalt a blue resembling Prussian blue--that, in fact, there can be obtained a Prussian blue with a base of cobalt instead of iron. In the moist state,... Cobalt Purples
are obtainable ranging from the richest crimson purple to the most delicate violet. We have produced them by wet and dry methods, varying in brilliancy and beauty, but characterised generally by want of body, and frequently by a smalt-like grittines... Cobalt Reds
There are obtainable from cobalt by different processes rose and red colours of more or less beauty and intensity, but all vastly inferior to those of madder, in whose absence alone they could gain a place on the palette. Durable as a rule, they are... Coffee Black
though little known and not on sale, has been strongly recommended by Bouvier as one of the best blacks that can be used. Soft without being greasy, light, almost impalpable, even before being ground, it gives tints of a very bluish gray when mixed ... Copper Blues
are now seldom or never employed as artists' pigments. The following are the principal varieties:-- ... Copper Borate
is obtained by precipitating sulphate of copper with borax, washing the residue with cold water, and, after drying, igniting it, fusion being carefully avoided. In this manner, a pretty yellowish green is produced, which upon longer ignition assumes... Copper Brown
varying in hue, is obtainable, in the form of prussiate, &c., but cannot be recommended, however made. ... Copper Chrome
may be prepared by several methods, but the colour is in no case so fine as Scheele's or Schweinfurt green, nor is it as stable. ... Copper Reds
A somewhat finely coloured red oxide is produced by exposing to a white heat for twenty minutes, a mixture of certain proportions of blue vitriol, mono-carbonate of soda, and copper filings. The product, however, is affected by impure air, and is ot... Copper Stannate
or Tin-Copper Green, equals in colour any of the copper greens free from arsenic. The cheapest way of making it is to heat 59 parts of tin in a Hessian crucible with 100 parts nitrate of soda, and dissolve the mass when cold in a caustic alkali. To ... Copper Yellow
Or chromate of copper-potassa, is of a bright yellow tint, not insoluble in water. It is discoloured both by foul gas and exposure. ... Cotton Seed Blue
Cotton seed oil is bleached by treatment with either carbonate of soda or caustic lime. In both cases, a considerable residue is left after drawing off the bleached oil. This residue is treated with sulphuric acid, and distilled at a high temperatur... Damonico
or Monicon, is an iron ochre, being a compound of raw Sienna and Roman ochre burnt, and having all their qualities. It is rather more russet in hue than the pigment known as orange or burnt Roman ochre, has considerable transparency, is rich and dur... Egyptian Blue
called by Vitruvius, Coeruleum, is frequently found on the walls of the temples in Egypt, as well as on the cases enclosing mummies. Count Chaptal, who analysed some of it discovered in 1809 in a shop at Pompeii, found that it was blue ashes, not pr... Ferrate Of Baryta
Produced by adding aqueous ferrate of potash to an excess of dilute solutions of baryta salts, has been described as carmine-coloured and permanent. We have not found it to be so--an experience which has evidently not been confined to ourselves; and... Frankfort Black
is said to be made of the lees of wine from which the tartar has been washed, by burning, in the manner of ivory black; although the inferior sort is merely the levigated charcoal of woods, of which the hardest, such as box and ebony, yield the best... French Prussian-brown
According to Bouvier, a colour similar to that of bistre, and rivalling asphaltum in transparency, is produced by partially charring a moderately dark Prussian blue; neither one too intense, which gives a heavy and opaque brownish-red, nor one too a... Gamboge Orange
On adding acetate of lead to a potash solution of gamboge, a rich bright orange is precipitated, which may be washed on a filter till the washings are colourless, and preserves its hue with careful drying. The orange which we thus obtained stood wel... Gambogiate Of Iron
Dr. Scoffern read a paper at the Meeting of the British Association of Science, in 1851, describing this combination as a rich brown, like asphaltum, but richer, as well as more durable in oil. It has not been, however, employed as a pigment, or at ... Gelbin's Yellow
Or chromate of lime, is a pale whitish yellow, poor in colour, partly soluble, and not at all to be depended on. ... Gold Blue
Gold purple, under the name of Purple of Cassius, was once very well known: a like compound of tin and gold may be made to yield a blue. Resembling indigo, the colour is not remarkably brilliant, and, unless several precautions are carefully observe... Gold Purple
Purple of Cassius, or Cassius's Purple Precipitate, was discovered in 1683 by Cassius of Leyden. It is a compound of tin and gold, best formed by mixing aqueous perchloride of iron with aqueous protochloride of tin, till the colour of the liquid has... Gold Reds
Many organic substances added to gold solutions throw down either the metallic gold or the red oxide, which then unites with the organic compound more or less decomposed and forms a red precipitate. Sugar, gum, the decoctions of cochineal, gamboge, ... Green Bice
or Green Verditer, is the same in substance as blue verditer, which is converted into green verditer by boiling. This pigment is one of the least eligible of copper greens. ... Green Ochre
By partially decomposing yellow ochre with prussiate of potash, we have produced a fine dark blue-green, resembling Prussian green, of great depth and transparency. There are, however, difficulties in the process; and the results do not warrant us i... Green Ultramarine
is French or artificial ultramarine before the final roasting. It is a somewhat bright bluish-green, becoming a dull greenish-blue on continued exposure. Chemically, it is not a bad colour; but artists generally have decided against it. ... Hypocastanum
or Chestnut Brown, is a brown lake prepared from the horse-chestnut. This now obsolete pigment is transparent and rich in colour, warmer than brown pink, and very durable both in water and oil; in the latter of which it dries moderately well. ... Indium Yellow
Whether the new metal indium will ever be found in sufficient quantity to render it practically useful remains to be seen. The most abundant source at present known is the Freiberg blende, 100,000 parts of which only yield from twenty-five to forty ... Iodine Blue
It is curious that iodine, which gives a yellow with lead, should also afford a blue with the same metal. When a solution of iodine in aqueous soda (carbonate of soda is not so good) is added to nitrate or acetate of lead-oxide, a transient violet-r...