Brief Description: The name calcite derives from its composition. Its chemical formula is CaCO3 and it belongs to the category Carbonate Minerals. Its lustre is vitreous or dull. It is colourless or has white colour. It occurs in various colour varieties as well, like ashy, red, green, blue, yellow, rosy, brown and black. Its specific gravity is 2.7 and it is transparent or semitransparent. Its hardness is 3 and its fusibility 7. It is found in prismatic, rhombohedral, scalenohedral crystals. Crystal system: triangular. The aggregates are solid, granular, compact, coralloid, stalactiform, rosette-like, lily-like etc. It effervesces with dilute, cold, hydrochloric acid. It constitutes the main component of limestone and marbles. It mainly occurs in sedimentary rocks. It is mainly used in Portland cement (75% CaCO3 and 25% Al2O3, SiO2) and lime manufacture. It is also used in construction, decoration, lithography and as fertilizer as well. 
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