Gemological Information for Calcite

Color:Transparent, Colorless and most other colors
Crystal Structure:Hexagonal (trigonal)
Refractive Index:1.486 to 1.658
Durability:Single Crystal=Poor Aggregates=Fair to Good
Similar Stones:Aragonite, Chalcedony, Coral, Alabaster
Treatments:Dyeing, Impregnation with Wax and Plastic, Irradiation
Country of Origin:Mexico, U.S.

Calcite Care

Ultrasonic Cleaning:Never
Steam Cleaning:Never
Warm Soapy Water:Usually Safe
Chemical Attack:Effervesces to Certain Acids
Light Sensitivity:Natural Colors Stable
Heat Sensitivity:Decrepitates at Higher Temps


  • Gem Reference Guide, Los Angeles: Gemological Institute of America, 1988. Pp. 41-43.
  • Schumann, Walter. Gemstones of the World, New York: Sterling Publishing, Co., 1977. Pp. 208.