A carbonate mineral consisting of a mixed
calcium-magnesium carbonate, CaCO3.MgCO3, crystallizing
in the rhombohedral system. It is usually white or colorless. The term is
also used to denote a rock with a high ratio of magnesium to calcium carbonate.
Dolomite is often found associated with limestone
or marble and in magnesium-rich metamorphic
rocks. Dolomitic limestone is a rock in which the limestone has been partially
replaced by dolomite.
Dolomite is used as an ornamental and building stone, and is a source of
magnesium. Hardness 3.5–4, relative
AND PLANETARY SCIENCE