Application:
Magnesium carbonate is mainly used in processing magnesium oxide by calcining. Magnesite and dolomite minerals are used to make refractory bricks. MgCO3 is also used in fire extinguishing,
flooring, cosmetics, dusting powder, fireproofing, and toothpaste.
Other applications are as filler material, smoke suppressant in plastics, a reinforcing agent in neoprene rubber, a drying agent, and colour retention in foods.
Magnesium carbonate, most often referred to as "chalk", is also used as a drying agent on athletes' hands in rock climbing, gymnastics, weightlifting and other sports in which a
firm grip is necessary.
As a food additive, magnesium carbonate is known as E504. Its only known side effect is that it may work as a laxative in high concentrations.
Magnesium carbonate is used in taxidermy for whitening skulls. It can be mixed with hydrogen peroxide to create a paste, which is spread on the skull to give it a white finish.
Magnesium carbonate is used as a matte white coating for projection screens.