Calcite is a very useful mineral in the glass industry since CaO performs the role of network modifier in glass manufacture. Ca2+ ions interfere with the network of the glass forming oxides like SiO2. Since the network gets disturbed, the melting point and viscosity of the glass forming oxide decreases.
Further, depending upon the concentration and composition of the network modifiers (normally a combination is of different modifiers are used), one can alter glass transition temperature, density, rigidity, durability and dimension stability.
Calcite powder for glass industry must compose of a high and consistent percentage of CaO and be devoid of color imparting impurities like Fe2O3 etc.
Rajasthan is an excellent source of high whiteness calcite. Anand Talc offers premium grade calcite powder taking due care of purity and consistency which is crucial for the glass industry to maintain uniformity in structure, color (rather, lack of color) and diaphaneity.
Following are the details of Anand Talc’s glass grade calcite. These specifications are approved by ISI and are subject to modifications as per customer requirement.