Product description: Heavy Calcium Carbonate (Heavy Calcium Carbonate, Ground Calcium Carbonate, GCC, Kotamite), is directly mechanically crushed from natural calcite, limestone, chalk, and shells; due to its sedimentation volume (1.1-1.9mL / g / g) is less than the light chemically produced Calcium carbonate sedimentation volume(2.4-2.8mL / g), it is called Heavy Calcium Carbonate. stable in the air, almost insoluble in water, soluble in alcohol. encountered dilute acetic acid, dilute hydrochloric acid, dilute nitric acid occurs intumescent and dissolved. heated to 898 ° C begins to decompose to calcium oxide and carbon dioxide.