Dolomite
Mineral CaMg(CO₃)₂; also the traditional name for a rock dominated by this mineral, for which dolostone is sometimes preferred.
Language and route: French dolomie, named in honour of Déodat de Dolomieu; later English dolomite. French dolomie, named in honour of Déodat de Dolomieu; later English dolomite
Literal gloss: named for Dolomieu
The name and its history
Théodore de Saussure (naming), following Déodat de Dolomieu (description) · 1792 naming; 1791 Dolomieu observation
- What does the word literally mean?
- Immediate source or formation: French dolomie, named in honour of Déodat de Dolomieu; later English dolomite. Literal gloss ‘named for Dolomieu’. This linguistic evidence is distinct from claims about the namer’s intentions.
- What did the original author mean?
- Dolomieu described Alpine carbonate material that resisted the vigorous acid effervescence expected of limestone; de Saussure’s 1792 dolomie commemorated his work. The nomenclatural act must not be credited to the observer.
- Why was the name needed?
- Geologists needed to distinguish a carbonate that behaved unlike calcite-rich limestone without having later crystallographic or geochemical knowledge.
- What evidence supported the original concept?
- Acid reaction and field occurrence underlay the old distinction; later chemical analysis and crystallography revealed ordered calcium-magnesium carbonate.
- How has geology changed the concept?
- Mineral dolomite and dolomite rock have diverged as concepts; the formation of extensive ancient dolostones still poses the dolomite problem.
Further historical context
Dolomieu described Alpine carbonate material that resisted the vigorous acid effervescence expected of limestone; de Saussure’s 1792 dolomie commemorated his work. The nomenclatural act must not be credited to the observer.
Geologists needed to distinguish a carbonate that behaved unlike calcite-rich limestone without having later crystallographic or geochemical knowledge.
Acid reaction and field occurrence underlay the old distinction; later chemical analysis and crystallography revealed ordered calcium-magnesium carbonate.
Mineral dolomite and dolomite rock have diverged as concepts; the formation of extensive ancient dolostones still poses the dolomite problem.
Editorial qualification
1792 original bibliography identified but not fully transcribed; do not conflate first observation, naming and modern mineral definition.
Related names
Sources
- Théodore de Saussure, Analyse de la dolomie (1792), Observations sur la Physique 40:161–173 — original publication identified bibliographically; relevant pages not directly transcribed
- History of Dolomieu and de Saussure naming, historical account — secondary chronological outline Dolomieu 1791 versus de Saussure 1792; original-passage verification still needed
- BGS RCS, dolostone and carbonate search results — modern carbonate versus dolostone compositional distinctions
- SLB Energy Glossary, dolostone — applied distinction between rock dolostone and mineral dolomite