Andalusite
Gemological Properties
| Gemological Information for Andalusite | |
|---|---|
| Color | Brownish to Yellowish Green, Green, Brown, rarely Pink |
| Crystal Structure | Orthorhombic |
| Refractive Index | 1.6345 - 1.643 |
| Durability | Fair to Good |
| Hardness | 7 to 7.5 |
| Varieties | Chiastolite - Features a Cross Pattern |
| Similar Stones | Tourmaline, Topaz, Barite, Apatite, Danburite, Chrysoberyl |
| Treatments | Heat Treatment |
| Country of Origin | Brazil, Sri Lanka |
| Andalusite Care | |
| Ultrasonic Cleaning | Use Caution |
| Steam Cleaning | Risky |
| Warm Soapy Water | Safe |
| Chemical Attack | None |
| Light Sensitivity | Stable |
| Heat Sensitivity | Check for Liquid Inclusions |
Online G&G articles on andalusite
- Winter 1948, An 85 ct. rough andalusite believed to be one of the finest, p. 124, 2pp.
- Winter 1960, A 32 ct. and a 20 ct. flawless cut andalusite (showing absorption spectrum), p. 121, 1p.
- Summer 1961, The Andalusite Absorption Spectrum, p. 185, 2pp.
- Fall 1976, Inclusions in Brazilian Andalusite, p. 201, 2pp.
- Winter 1980, Inclusions in Andalusite – A Comparison of Localities, by John I. Koivula, p. 401, 4pp.