dolomite

Dolomite is a word from geology. It most often refers to a carbonate mineral made of calcium magnesium carbonate, and by extension to a sedimentary rock that is rich in that mineral. Because it often resembles limestone, people sometimes confuse the two, but dolomite usually contains much more magnesium and can behave differently under chemical testing. It commonly forms in marine environments and can preserve clues about ancient seabeds, buried sediments, and changes that took place over immense spans of time.

The name is linked to Déodat de Dolomieu, an 18th-century French geologist and naturalist. In his honor, the mineral came to be known as dolomite, and the famous mountain region where this rock is widespread became known as the Dolomites. That means the singular word usually points to the mineral or rock, while the plural form, "the Dolomites," refers to the mountain range in northern Italy.

In practical use, dolomite matters well beyond textbooks. It is quarried for construction materials, used in road base and cement-related applications, added in some glass and ceramic processes, and spread on fields to help adjust overly acidic soil. In everyday language, the word may also suggest the pale, dramatic peaks of the Dolomites, especially in writing about travel, climbing, or Alpine landscapes. Even so, its central meaning remains geological: a mineral, and the rock built from it.