Pigments through the Ages - Manufacture Recipes

How Red Ochre is made:

Origin: natural earth and artificial	Red ochre consists of silica and clay owing its color to iron oxide. It is found throughout the world, in many shades, in hues from yellow to brown, and faint blue. The best brown ochre comes from Cyprus.
	Red and yellow ochre pigments abound at the surface in Minas Gerais, Brazil. Pigments like these were readily made into paints by prehistoric peoples (such as the nearby Santana do Riacho, Lago a Santa) who would then paint with their fingers or with vegetable paint brushes.

Natural variety of pigment	Colored earth is mined, ground and washed, leaving a mixture of minerals - essentially rust-stained clay. Ochre can be used raw (yellowish), or roasted for a deeper (brown-red) color from loss of water of hydration. Produces a quick-drying oil paint.
Artificial variety of pigment	Synthetic red Iron oxide pigments were first made in a laboratory setting by the 18th century. This pigments were given the name Mars Red. These pigments contained all the properties of their counterparts, i.e. Natural Iron Oxide Pigments. Form 19th century, the manufacturing of these synthetic iron oxide pigments started on regular basic. Gradually, the improvements have been taken place with every production process. In the early 1920, the yellow synthetic iron oxide pigments (Mars Yellow) were produced for the first time. Vital improvement processes have been taking place along with its production and still improvement processes are continued. To produce synthetic iron oxide pigments, iron salts or iron compounds are decomposed. By precipitating of iron salts and reducing the organic compounds by iron, pigments of synthetic iron oxide can be prepared.

Illustration of the process:

Picking iron oxide by hand in Hiwassee, Virginia. Mining for pigments is desirable work in Virginia, where the quarry mines are open pits and above ground, and relatively safe.

Mining iron oxide with a mechanized scoop.