Grossular (Var.: Hessonite), Clinochlore. Locality: Bellecombe, Châtillon, Aosta Valley, Italy (Locality at mindat.org). Size: 7.4 x 3.8 x 2.6 cm. Beautifully gemmy and lustrous, cherry-red hessonite (grossular) garnets with complimentary, tabular, green clinochlore crystals form an outstanding and impressive specimen from a famous Italian locality - Bellecombe in the Aosta Valley. Super rich material from this classic locale. by Rob Lavinsky, iRocks.com – CC-BY-SA-3.0 [CC-BY-SA-3.0], via Wikimedia Commons
Clinochlore Value
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Clinochlore Information
| Data | Value |
| Name | Clinochlore |
| Varieties | Kämmererite, Seraphinite |
| Crystallography | Monoclinic, pseudo hexagonal |
| Refractive Index | 1.571 - 1.600 |
| Colors | Sheridanite: Blackish green, Bluish green, Olive green; Kämmerite: Red, Purple |
| Polish Luster | Vitreous |
| Fracture Luster | Vitreous, pearly |
| Fracture | Uneven |
| Hardness | 2 - 2.5 |
| Toughness | Good |
| Specific Gravity | 2.55 - 2.75 |
| Birefringence | Sheridanite 005 – .011, Kämmerite .003 |
| Cleavage | Perfect 1 direction |
| Stone Sizes | Faceted Kämmerite to 2 carats, Sheridanite cabs to large |
| Heat Sensitivity | Yes |
| Enhancements | None |
| Transparency | Transparent to translucent |
| UV Long | None |
| UV Short | None |
| Absorption Spectrum | Not diagnostic |
| Phenomena | None known |
| Formula | (Mg,Fe++)5Al(Si3Al)O10(OH)8 |
| Pleochroism | Sheridanite: Strong, pale green, colorless, pale yellowish green, pale brownish yellow; Kämmerite: Strong, violet, red |
Clinochlore is a family of minerals in the chlorite group. Varieties include Colerainite, Kämmerite, Pennine, Penninite, Prochlorite, Ripidolite, and Sheridanite. To date, only Kämmerite and Sheridanite are known to have been cut as gemstones.
Names
- Clinochlore from the Greek klino – “oblique” and chloros – ” green.”
- Ripidolite from the Greek rhipis – “fan” and lithos – “stone.”
- Pennine from the Pennine Alps, Italy
Variety Names
- Clinochlore – green
- Colerainite
- Kammererite – Red to purple
- Pennine
- Penninite
- Prochlorite
- Ripidolite
- Sheridanite Dark green, rich in chromium
