This fragile mineral has a distinct cleavage plane and is rarely faceted as a gemstone. Occurring in a columnar form with striated faces along the length of the column, brown, yellow, and green specimens are possible. Yellow, green, or brown pleochroism is observed. Rock mixtures containing epidote are often tumbled and referred to as unakite. Epidote can be found in the French and Austrian Alps, Russia, Pakistan, Alaska, Italy, Mozambique, and Mexico.
Gemological Information Epidote
| Color: | Dark Brown, Light to Dark Green, Yellow & Black |
| Crystal Structure: | Monoclinic |
| Refractive Index: | 1.729 – 1.768 |
| Durability: | Fair to Poor |
| Hardness: | 6 to 7 |
| Family: | |
| Similar Stones: | Idocrase, Kyanite, Zoisite |
| Treatments: | None Known at this Time |
| Country of Origin: | U.S., Austria, Italy, France, Finland, Czech Republic, Finland, Myanmar, Kenya, Mexico, Brazil |
Epidote Care
| Ultrasonic Cleaning: | Risky |
| Steam Cleaning: | Never |
| Warm Soapy Water: | Safe |
| Chemical Attack: | Decomposed by Hydrofluoric Acid and Slowly Decomposed by Hot Hydrochloric Acid |
| Light Sensitivity: | Stable |
| Heat Sensitivity: | Fuses with Heat |
Sources
- Gem Reference Guide, Los Angeles: Gemological Institute of America, 1988.
- Hall, Cally. Gemstones, Smithsonian Handbooks. London, DK Penguin Random House, 2021.