What does dolostone mean?
Dolostone is a sedimentary rock composed predominantly of the carbonate mineral dolomite, a calcium magnesium carbonate. It closely resembles limestone in appearance and origin, and most dolostone is believed to form when magnesium-rich waters chemically alter pre-existing limestone, replacing some calcium with magnesium. Because it is typically harder and less soluble than limestone, dolostone often forms prominent ridges, escarpments, and cliff-forming units in the landscape, and it serves as an important source of crushed stone, aggregate, and lime products. The name derives from the French geologist Déodat de Dolomieu, whose eighteenth-century studies of these rocks in what are now the Italian Alps gave his name to both the mineral and the Dolomite Mountains themselves. Dolostone is chiefly encountered in geology textbooks, field guides, and technical reports on groundwater, petroleum reservoirs, and quarrying, making it a specialized rather than everyday vocabulary item.
nounA sedimentary carbonate rock composed predominantly of the mineral dolomite, similar to limestone but richer in magnesium. It forms chiefly through the alteration of limestone by magnesium-rich fluids.
- A sedimentary carbonate rock consisting mainly of the mineral dolomite, formed largely by chemical alteration of limestone.
"The cliffs along the Niagara Escarpment are formed largely of resistant dolostone."
"Much of the aquifer beneath the city lies within fractured dolostone layers."
"Quarries in Ontario extract dolostone for use as aggregate and building stone."
The plural is used when referring to multiple distinct bodies, varieties, or occurrences of the rock; as a material noun, 'dolostone' is usually uncountable.
"The region's dolostones range in age from Ordovician to Silurian."
Dolostone is named after French geologist Déodat de Dolomieu, who first described it in the mountains that now bear his name — the Dolomites.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of dolostone
The word 'dolostone' is a modern compound combining 'dolo-' (from 'dolomite') with 'stone.' The underlying eponym honors Déodat Gratet de Dolomieu (1750–1801), the French geologist who first described the rock and its characteristic mineral in the late eighteenth century while studying the alpine region now called the Dolomites. Closely related terms include 'dolomite,' 'dolomitic,' and the place name 'Dolomites,' all tracing back to the same source.
How dolostone is actually used
A technical term used almost exclusively in geology, earth science, and related professional contexts; it is rare in everyday speech. Some older or regional sources loosely call this material 'dolomite,' though careful usage reserves 'dolomite' for the mineral itself.
Easily confused with dolostone
Limestone is made mostly of calcium carbonate (calcite), whereas dolostone contains a high proportion of magnesium-bearing dolomite and is typically harder and less reactive with dilute acid.
Dolomite is the individual mineral (calcium magnesium carbonate), while dolostone is the rock composed largely of that mineral.