calcite

Iceland SPAR is often used as a polarizing prism because of its birefringent properties. If cut into a columnar shape in a certain way, it can be used as a microscope prism to detect the optical properties of minerals. The quality requirements must be: colorless and transparent, without internal bubbles or cracks, without twin crystals or distortions, and above 0.5 "(12.5mm) cubic. General calcite used in chemical, cement and other industrial raw materials. Calcite is used as a flux in the metallurgical industry and in the construction industry to produce cement and lime. Also used in plastics, paper, toothpaste. Used as filler in food. Calcite is added in the production of glass, the resulting glass will become translucent, especially suitable for making glass lampshades.