STC has been in Various Mineral & Metals business as a family concern since 1998. The Company has acquired 5 mining leases in various District of Gujarat State, India, having total area of about 45 hectares, over & above 36 hectares being possessed in name of its associated company as well a fresh application for about 20 hectares to Govt. during 2001.
Minerals Lease : Bauxite, Red Ocher, Yellow Ocher, Lime Stone And Natural Gypsum
Yellow Ocher other name is Goethite, limonite, raw sienna, yellow earth, yellow iron oxide, yellow hydrated oxide and iron hydroxide pigment, The main color giving component of natural yellow ochre (ocher, yellow earth) is limonite which is not a single mineral but a mixture of several iron-containing minerals among them goethite, akageneite, lepidocrocite, and jarosite, goethite (iron oxide hydroxide α-FeOOH) being the main component.
Iron oxides are stable at high temperatures but not resistant against acids. The pigment is absolutely stable as is documented by the cave paintings still in excellent condition after many thousands of years. It is compatible with all other pigments and is often used in mixture with other paints.
Paint & Pharmaceutical Industries
Oil Absorption and Grinding
Ocher absorbs a moderately high amount of oil. The oil absorption ratio is 30–35 parts by weight of linseed oil to 100 parts by weight of pigment. If the measurement were grams, this pigment would require 30-35 grams of pigment to grind 100 grams of linseed oil to form a stiff paste. It slows the drying of oil paint, but forms a good film.
|Silica As SiO2||%||16 to 21||IS : 2000:P-2:1985|
|Magnesium Oxide As MgO||%||2 to 25||IS : 5949 : 1990|
|Calcium Oxide As CaO||%||27 to 32||IS : 5949 : 1990|
|Iron Oxide As Fe2O3||%||11 to 18||IS : 2840 : 2002|
|Alumina Oxide As Al2O3||%||10 to 15||IS : 2840 : 2002|
|Sodium As Na2O||%||0.01 to 0.20||IS : 9497 : 1980|
|Potassium As K2O||%||0.25 to 1.15||IS : 9497 : 1980|
|Loss of Ignition||%||25 to 28||IS : 2840:2002|
|Sizes||%||0-200mm & 100 + mesh|