One of the most common chemicals connected to calcium is called “carbonate”, and together they make calcium carbonate. Calcium carbonate is in eggshells, seashells, a rock called marble, and in ...

Calcium carbonate is an over-the-counter product with ... have less calcium than the forms mentioned above. Knowing which supplement to take is a conversation with your medical provider.

Limited research suggests that magnesium aspartate, citrate, lactate, or chloride may be better absorbed than other forms.