Superfine heavy calcium carbonate It is white power ,insoluble in water ,dissolvable in acid and widely used in dope paint plastic rubber pottery and porcelain ,paper making and ect as the filling materials . item calcium carbonate (CaCO3) content ?????????????????????????????? ???98% Iron content (Fe) ????????????????????????????????. ???.1% Muriatic acid insolubles content?????????????????????????? ???.2% Moisture and volatile content ???????????????????????????. ???.3% Density (g/cm3) ????????????????????????????????????2.9 Mohs hardness ??????????????????????????????????? ???.0 Whiteness ???egree??? ??????????????????????????????????? ???4.0 Oil absorption (ml/g) ????????????????????????????????????. 16-25 Ph ??????????????????????????????????? 8-9 Heavy metal???b??????????????????????????????????????????.001