Dlarsen":3earf2dy said:
Iv never heard of colloidal powder? Is it from Tracie?
Is simply very fine powder of CaC03 formed by precipitation from saturated solution which is then "extracted" and dried.
Calcium carbonate has a very low solubility in pure water (15 mg/L at 25°C).
Some manufacturers use ground oyster shells or ground limestone then sieve the grit to make a CaCO3 powder.
The colloidal CaCO3 is much smaller in particle size (about 10 nm) cf ground CaCO3 which should be sold under 250 microns (about the size of flour particles).
The colloidal CaCO3 particles are much more readily digested and metabolized.