Precipitated Calcium Carbonate is obtained from Limestone calcination over 900°C. Limestone is burned, to form lime from which pcc is obtained by consequtive chemicals reactions under pressure.Since chemical reactions are concerned,impurities are eliminated by outstanding chemical process control to form a ideal whiteness,particle size and crystal shape. PCC crystals have uniform crystal shape and particle size distribution, not like Ground Calcium Carbonate. 

PCC production technique can be illustrated as follows ; 
* CaCO3  CaO + CO2 (calcination Process) 
* CaO + H2O  Ca(OH)2 (milk of lime) 
* Ca(OH)2 + CO2  CaCO3 + H2O (Precipitation)