By Cameron Delaney | Updated Mar 24, 2022
Magnesium carbonate (MgCO₃) is a fine, odorless white powder that serves a wide range of industrial and pharmaceutical purposes.
The compound’s formula, MgCO₃, makes it a mildly alkaline substance rather than acidic. Its crystalline structure allows it to remain stable under typical storage conditions.
In nature, magnesium carbonate is found in the minerals magnesite and dolomite, as well as in many limestones. Industrially, it is produced by reacting magnesium salts with carbon dioxide.
Manufacturers employ magnesium carbonate as a heat‑insulating agent for boilers and piping, and it is a key ingredient in antacids, laxatives, and various dietary supplements. The compound also functions as an additive in food products, cosmetics, glass, ink, and rubber manufacturing.
Magnesium carbonate is insoluble in water, but it reacts with dilute acids, releasing carbon dioxide and forming soluble magnesium salts.
In 1911, the Morton Salt Company added magnesium carbonate to table salt to prevent clumping in humid conditions—a strategy that gave rise to the slogan “When it rains, it pours.”
