Gemological information

Gemological Information for Thulite, Zoisite
Color Pink (Sometimes with White Streaks)
Crystal Structure Orthorhombic
Refractive Index 1.691 to 1.700
Durability Fair to Poor
Hardness 6 to 7
Similar Stones Rhodonite, Hydrogrossular Garnet
Treatments None Known
Country of Origin Tanzania, Austria, Germany, Italy, Mexico, Switzerland, U.S.
Thulite Care
Ultrasonic Cleaning Never
Steam Cleaning Never
Warm Soapy Water Safe
Chemical Attack Hydrochloric and Hydrofluoric Acids Attack
Light Sensitivity Stable
Heat Sensitivity Jeweler's Torch may Fuse


Gem Reference Guide, Los Angeles: Gemological Institute of America, 1988. Pp. 262-264.

Schumann, Walter. Gemstones of the World, New York: Sterling Publishing, Co., 1977. Pp. 160.