The staining power, brilliance and fineness of texture are the main properties by which an ochre is judged for its quality and value in industry. The tint should be wholly of the inorganic ingredient.
The principal use of ochre is as tinting colours. It is used for colour washes, distemper and oil paints. It is also used in making coloured paper. For this particular use ochre and china-clay or soapstone, after dissolving in water in paste form, are acreened and added in the beater for the prepareation of coloured paper pulp. Red oxide pigments are widely used as primers for painting structural steel, automobile bodies, ship bottoms, etc. Red ochre Powder is also a important constituent of a number of abrasives and pigments.
Used in every type of paint, primer, powder, coating etc.
One of the important raw material in manufacturing of Clinker.
Tiles & Ceramic Industry
Plastic & Rubber
Yellow ochre, is a form on hydrated iron(III) hydroxide (FeO(OH) • nH2O). It's usually called limonite but limonite is not a true mineral name (although it's commonly used by geologists). Limonite is actually a mixture of different iron hydroxide minerals which typically form when iron-rich water encounters atmospheric oxygen (and typically helped along by Fe-fixing bacteria) - hence the name "bog iron" for sedimentary deposits of this mineral.
Red ochre is derived from hematite (Fe2O3) which is oxidized iron and rusty red in color (rust and hematite are essentially the same thing). The name hematite comes from αἷμα (haima) the Greek word for blood (same root as hemoglobin) because of the color. Red oxide usually contains about 70% Fe2O3
SiennaSienna is a brownish yellow containing about 60% Fe2O3 with some quantity of manganese oxide. It is named after sthe town of Sienna in Italy where a large deposit is located. Sienna is marketed in the raw and burnt (calcined) states.
Umber is a natural brown or reddish-brown earth pigment that contains iron oxide and manganese oxide. It is darker than the other similar earth pigments, ochre and sienna. In its natural form, it is called raw umber. When heated (calcined), the color becomes more intense, and the color is known as Burnt umber.
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