Red Precipitate
: ON THE PRIMARY, RED.Or mercuric oxide, may be obtained either of a brick-red or
orange-yellow colour. It is destroyed by impure air, and on exposure to
sunshine gradually turns black, being superficially decomposed into
oxygen and metallic mercury or mercurous oxide.
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Patent Yellow
... Peach Black
or Almond Black, made by burning the stones of fruits, the shell of the cocoa-nut, &c., is a violet-black, once much used by Parisian artists. Bouvier believes it to be a good black, but at the same time sensibly asks, of what use is it to have a bl... Peganum Harmala
The seeds of which afford a red colour, has been investigated by the French, but described as inferior to existing reds both in brilliancy and stability. ... Persulphomolybdates
The metallic compounds formed by the combination of persulphomolybdic acid with a base are pulverulent, in many cases of a red colour, and for the most part insoluble in water. With barium, the acid furnishes a yellowish-red powder, insoluble in, bu... Platinum Blue
With mercurous nitrate, the platinocyanide of potassium forms a thick smalt blue, and the platinidcyanide a dark blue precipitate. The compound is a mixture of platino- or platinidcyanide of mercury and mercurous nitrate. Upon the presence of the la... Platinum Yellow
Our own opinion of this costly preparation is that the good qualities of the product do not justify its price. It may be obtained as a bright, rich, deep yellow, of considerable transparency; but the colour is acted upon by foul gas and exposure. Ev... Prussian Black
The same Prussian blue which gives a brown when burnt in the open air, yields a black when calcined in a close crucible. Very intense, very soft and velvety, and very agreeable to work, this bluish-black dries much more promptly than most other blac... Prussian Purple
A prussiate of iron is obtainable of a violet hue, affording good shadow tints and clear pale washes. It has not, however, been introduced as a pigment, as ordinary Prussian blue tinged with red furnishes a similar colour. ... Prussiate Of Copper
differs chemically from Prussian blue only in having copper instead of iron for its basis. It varies in hue from russet to purple brown, is transparent and deep, but, being very liable to change in colour by the action of light and by other pigments... Purple Black
is, or rather was, a preparation of madder, of a deep purple hue approaching black. Powerful and very transparent, it glazed and dried well in oil, and was a durable and eligible pigment. Its tints with white lead were of a purple cast. ... Purple Brown
is a refuse manufacture from Indian red washings. A dull, heavy, coarse colour, it belongs to the class of common pigments which are unexceptionable for decorative painting, but scarcely suited to the higher branches of art. As this work professes s... Quinine Green
is rather adapted for a dye than an artist-colour. It is furnished by acting on quinine with hypochlorite of lime, hydrochloric acid, and ammonia, successively. Thus prepared, the green resembles a resin, insoluble in water, but soluble in alcohol, ... Red Chalk
The colouring matter of which is sesquioxide of iron, is used as a crayon. Some specimens are excessively hard, so much so that they are difficult to crush, even in an iron mortar; while others have the consistence of the softest iron-ochres. They v... Red Precipitate
Or mercuric oxide, may be obtained either of a brick-red or orange-yellow colour. It is destroyed by impure air, and on exposure to sunshine gradually turns black, being superficially decomposed into oxygen and metallic mercury or mercurous oxide. ... Roman Green
brought from Rome some years back by a President of the Royal Academy, appeared to be a mixture of Prussian blue and Dutch or Italian pink. It was a fugitive compound, which became blue in fading. ... Rose Pink
Is a coarse kind of lake, produced by dyeing chalk or whitening with decoction of Brazil wood, peachwood, sapan, bar, camwood, &c. It is a pigment much used by paper-stainers, and in the commonest distemper painting, &c., but is too perishable to me... Rouge
The rouge vegetale of the French, is a species of carmine, prepared from safflower or carthamus, which is the flower of a plant growing in the north of Africa, India, and other warm climates. Safflower yields two colours--a valueless yellow which di... Rubens' Brown
still in use in the Netherlands under this appellation, is an earth of a lighter colour and more ochrous texture than the Vandyke brown of English commerce: it is also of a warmer or more tawny hue than the latter pigment. Beautiful and durable, it ... Rufigallic Red
When a duly proportioned mixture of gallic acid and oil of vitriol is carefully and gradually heated to 140 deg., a viscid wine-red liquid results. If this be poured into cold water, after cooling, a heavy brown-red granular precipitate is formed, s... Sandal Red
We have kept this separate from other reds derived from woods, because it is said (by Professor H. Dussance) to be obtainable not only equal in beauty and brightness to carmine, but of greater permanence. The process of preparation is as follows:--T... Sandal Wood Purple
Sandal wood contains about 16 per cent. of colouring matter, soluble with difficultly in water, but readily dissolved by alcohol. From the latter solution, chloride of tin throws down a purple, and sulphate of iron a deep violet precipitate; neither... Saunders Blue
... Schweinfurt Blue
or Reboulleau's Blue, is prepared by fusing together equal weights of ordinary arseniate of protoxide of copper and arseniate of potash, and adding one-fifth its weight of nitre to the fused mass. The result is, so to speak, a sort of blue Scheele's... Silicate Of Baryta
One part of silica heated to whiteness with three parts of baryta, yields a pale green solid mass, permanent, but deficient in colour when ground. It might be employed in enamelling. ... Silver Red
By adding monochromate of potash to an acid solution of nitrate of silver, a particularly fine ochre-red is obtained. It is, however, apt to be injured both by foul air and exposure. ... Sorgho Red
Some nine years back there was found to be a carmine colouring matter in most parts of the Chinese sorgho, chiefly in the unpressed stem. The red, which is extracted in an impure state, is dissolved in weak potash-ley, thrown down by sulphuric acid,...