Precipitated Calcium Carbonates (PCCs) are manufactured or synthesized calcium carbonates, which can be prepared in many different crystal sizes and shapes. For an introduction to what PCCS are and how they are made.

A special category of PCC is the ultrafine PCC, or as it is now more commonly known, the nano PCC. Nano particles are those which are less than 100 nanometers or 0.1 microns in size. To help judge what this means: a human hair is between 40 to 120 microns thick. To give you an idea of how small this is you would have to line up 400 ultrafine PCC particles, side by side, to make a line of particles the width of the finest human hair. Very small, indeed!