Garnet Minerals
Name and Composition - The garnet are silicates of di & trivalent metals with general formula R32+ R23+ (SiO4)3 where R2+ is Ca, Mg, Fe & Mn & R 3+ is Fe, AI, Cr or Ti. The six varieties of garnets are grossularite, pyrope, almandine, spesartrite, andradite & uvarovite.
Physical Properties - The garnet crystalises in cubic system and occurs as rhombo dodecahedran & trapezohedran crystals or combination of both, the colour is pale green, yellow, pink, crimson red, brownish red & dark brown sp.gr. 3.5 to 4.19 & hardness 7 to 7.5.
Mode of Occurrence - Garnet is found associated with different igneous & metamorphic rocks. Generally it occurs in garnetiferous mica schist, as fine to coarse (as large as cricket ball size) crystals.
Uses - Vastly used to manufacture emery coated abrasive paper, cloth, discs for grinding and finishing glass, wood rubber, plastic, leather and metal products. In powder form, it is used in making lapping & buffing compounds; fine powder is used in non-skid floors, paints, spark plugs cleaning and plate glass grinding. The clear, flawless and rich coloured deep blood red and maroon green garnets are used as semi precious stones (gems).
Mineral based Industries – Abrasives (paper, cloth, disc) and gem processing units.
Industrial Prospects – Abrasive and gem processing units.
Physical Properties
Hardness
Sp. gr.
Fracture
Cleavage
Sp. gr.
Fracture
Cleavage
7 to 7.5
3.5 to 4.19
Conchoidal to uneven
Indistinct
3.5 to 4.19
Conchoidal to uneven
Indistinct
Chemical Properties
Refractive index
Streak
Cleavage
Streak
Cleavage
1.72 – 1.94
White
Indistinct
White
Indistinct
Indian Minerals
Metallic Minerals
Cadmium Ore
Copper Ore
Lead Ore
Zinc Ore
Iron Ore
Manganese Ore
Tungsten Ore
Bauxite Ore
Limestone and Dolomite
Limestone
Dolomite
Fertilizer Minerals
Gypsum
Pyrite
Rock Phosphate
Saltpeter
Fuel Minerals
Lignite
Glass and Ceramic Minerals
Ball Clay
China Clay
Feldspar
Fire Clay
Kyanite
Quartz
Quartzite
Silica Sand
Precious and Semiprecious Minerals
Aquamarine
Emerald
Industrial Minerals
Asbestos
Barytes
Bentonite
Calcite
Fluorite
Fuller's Earth
Garnet
Graphite
Magnesite
Mica
Mill Stone
Ochre
Pyrophylite
Siliceous Earth
Silimanite
Soapstone
Vermiculite
Wollastonite
Dimensional and Building Stone
Granite
Limestone - Flaggy
Marble
Rhyolite
Sandstone
Serpentinite
Shale/Schist/Phyllite
Slate