Heavy calcium carbonate, referred to as heavy calcium, is made of natural carbonate minerals such as calcite, marble and limestone. It is a kind of common powder inorganic filler, which has the advantages of high chemical purity, high inertia, difficult chemical reaction, good thermal stability, no decomposition below 400 ℃, high whiteness, low oil absorption, low refractive index, soft, dry, no crystal water, low hardness, low abrasion value, ~, tasteless, odorless, good dispersion, etc