Gemological information

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
Hardness 3
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.