Red Ochre is a name proper rather to a class than to an individual pigment, and comprehends Indian red, light red, Venetian red, scarlet ochre, Indian ochre, redding, ruddle, bole, etc, beside other absurd appellations, such as English vermilion and Spanish brown, or majolica.

Almagra, the Sil Atticiim of the antients, is a deep red ochre found in Andalusia, as is also their terra Sinopica, etc. or Armenian bole, dug originally in Cappadocia, and now found in New Jersey and elsewhere under the name of bloodstone.

The red ochres are, for the most part, rather hues and tints than definite colours, or more properly classed with the tertiary, semi-neutral, and broken colours; they are, nevertheless, often very valuable pigments for their tints in dead colouring, and for their permanence, etc. in water, oil, crayons, and fresco, and in a low tone of colouring have the value of primaries. The greater part of them are native pigments, found in most countries, and very abundantly and fine in our own; but some are productions of manufacture, and we have produced them in the variety of nature by art. The following are the most important of these pigments, most of which are available in enamel-painting.

1. Indian Red

Indian Red, according to its name, is brought from Bengal, and is a very rich iron ore, or peroxide of iron. It is an anomalous red, of a purple-russet hue, of a good body, and valued when fine for the pureness and lakey tone of its tints. In a crude state it is a coarse powder, full of extremely hard and brilliant particles of a dark appearance, sometimes magnetic, and is greatly improved by grinding and washing over. Its chemical tendency is to deepen, nevertheless it is very permanent; neither light, impure air, mixture with other pigments, time, nor fire, effecting in general any sensible change in it: but being opaque, and not keeping its place well, it is of course not fit for glazing. This pigment varies considerably in its hues, - that which is most rosy being esteemed the best, and affording the purest tints: inferior red ochres have been formerly substituted for it, and have procured it a variable character, but it is now obtained abundantly, and may be had pure of respectable colourmen.

Persian red is another name for this pigment, for which we have often heard the late presidents, Mr. West, Sir Thomas Lawrence, and others, well experienced in its use, express the highest esteem.

2. Light Red

Light Red is an ochre of a russet-orange hue, principally valued for its tints. The common light red is brown ochre burnt, but the principal yellow ochres afford this colour best; and the brighter and better the yellow ochre is from which this pigment is prepared, the brighter will this red be, and the better flesh tints will it afford with white. There are, however, native ochres brought from India and other countries which supply its place, some of which become darkened by time and impure air; but in other respects light red has the general good properties of other ochres, dries admirably, and is much used both in figure and landscape painting. It affords also an excellent crayon. See Orange Ochre.

3. Terra Puzzoli

Terra Puzzoli, a volcanic production, is a species of light red, as is also the.

4. Carnagione

Carnagione of the Italians, which differs from the above only in its hue, in which respect other variations and denominations are produced by dressing and compounding.

5. Venetian Red, Or Scarlet Ochre

True Venetian red is said to be a native ochre, but the colours sold under this name are prepared artiricially from sulphate of iron, or its residuum in the manufacturing of acids. They are all of redder and deeper hues than light red, are very permanent, and have all the properties of good ochres.

Prussian red, English red, and Rouge de Mars, are other names for the same pigment.

6. Spanish Red

Spanish Red is an ochre differing little from Venetian red.