- Registry number
- CHEM-003
- Preferred designation
- Calcium carbonate
- Common names
- Calcite · limestone · chalk
- Chemical formula
- CaCO₃
- CAS registry
- 471-34-1
- PubChem CID
- 10112
- Formula mass
- 100.09 g/mol
- Class
- Alkaline-earth carbonate
Description & appearance
White powder or crystalline mineral; very low water solubility.
Occurrence & historical provenance
Major constituent of limestone and marble; also present in chalk, shells, and many sedimentary deposits.
Established uses
Construction materials, cement feedstock, paper and paint fillers, and antacid formulations.
Hazards & handling context
Ordinary handling is comparatively low hazard; dust exposure and material-specific impurities still matter.
Important distinctions
Calcite and aragonite share CaCO₃ chemistry but differ in crystal structure. Limestone is a rock, not always chemically pure calcium carbonate.
Source ledger
The following reference records were consulted for chemical identity and general descriptive claims. Industrial grades, formulations, and mixtures may have different hazard profiles.
Catalogued 2026-11-11 · PyreArms 0.2.0. This is an authored reference entry, not a certificate of laboratory analysis.