Lee Universal Enterprises

Description : Red Ochre (Earthy Haematite)

Class : Oxides & Hydroxides

The earthy form of haematite is red ochre, yellow ochre is an earthy from of limonite (a mix of iron hydroxides and oxides). Both red and yellow ochre is used as a pigment and is often used as body paint with a spiritual significance by many tribal peoples across the world.

A pigment is a material that changes the color of light it reflects as the result of selective color absorption. This physical process differs from fluorescence, phosphorescence, and other forms of luminescence, in which the material itself emits light. Many materials selectively absorb certain wavelengths of light. Materials that humans have chosen and developed for use as pigments usually have special properties that make them ideal for coloring other materials. A pigment must have a high tinting strength relative to the materials it colors. It must be stable in solid form at ambient temperatures.

For industrial applications, as well as in the arts, permanence and stability are desirable properties. Pigments that are not permanent are called fugitive. Fugitive pigments fade over time, or with exposure to light, while some eventually blacken.
ISO standards define various industrial and chemical properties, and how to test for them. The principal ISO standards that relate to all pigments are as follows:
ISO-787 General methods of test for pigments and extenders ISO-8780 Methods of dispersion for assessment of dispersion characteristics

Many manufacturers of paints, inks, textiles, plastics, and colors have voluntarily adopted the Colour Index International (CII) as a standard for identifying the pigments that they use in manufacturing particular colors.