PR101—Indian Red
Pigment Type
synthetic
Chemical Name
iron oxides (synthetic), iron oxide, silica, alumina, lime, and magnesia or hydrated iron oxide
Chemical Formula
Fe2O2 or Fe2O3 • H2O
Properties
Indian Red is a slightly duller, deep brick hue with a bluish undertone, made from red iron oxide. It is very dense and opaque, with excellent tinting strength and covering power. It is dependable when mixing with all other permanent pigments and yields good flesh tints when mixed with Zinc White. It is the synthetic version of PR102, which is a pigment made from earth reds, or natural red iron oxides, and the names applied to PR101 and PR102 often overlap. The synthetic red iron oxides have mostly replaced natural red iron oxides and are brighter, stronger, finer, and more permanent. Indian Red is the highest grade bluish shade. Light Red, English Red, and Venetian Red are yellowish shades. Mars Violet is a dull and subdued bluish or purplish oxide. Indian Red produces a range of violet hued grays when mixed with Cerulean Blue, and it is the best neutralizer for iron blues like Prussian Blue.
Permanence
Indian Red is very lightfast with excellent permanence.
Toxicity
Indian Red has no significant hazards.
History
Natural red iron oxide comes from the mineral ore hematite, called bloodstone by the ancient Greeks from the word hema, meaning blood. It is one of the oldest pigments, has been used by every major civilization, and was an important mineral for medieval alchemists. It was not widely used in artists' materials until the 17th century and was not produced in large quantities until the 18th century.
Alternate Names
Caput Mortuum, Colcothar, English Red, Light Red, Mars Red, Mars Violet, Morelle Salt, Pompeian Red, Red Iron Oxide, Red Oxide, Sinopia, Spanish Red, Terra Rosa, Tuscan Red, Venetian Red, Venice Red.
