Clinochlore Value, Price, and Jewelry Information

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

Clinochlore Information

Data Value
Name Clinochlore
Varieties Kämmererite, Seraphinite
Stone Sizes faceted Kämmerite to 2 carats, Sheridanite cabs to large
Heat Sensitivity yes
Formula (Mg,Fe++)5Al(Si3Al)O10(OH)8
Colors Sheridanite: Blackish green, Bluish green, Olive green; Kämmerite: Red, Purple
Fracture Uneven
Hardness 2 - 2.5
Cleavage Perfect 1 direction
Wearability Poor
Crystallography Monoclinic, pseudo hexagonal
Refractive Index 1.571-1.600
Birefringence Sheridanite 0.005–0 .011, Kämmerite 0.003
Luminescence None.
Luminescence Present No
UV Long none
UV Short none
Absorption Spectrum Not diagnostic.
Pleochroism Sheridanite: Strong, pale green, colorless, pale yellowish green, pale brownish yellow; Kämmerite: Strong, violet, red
Optics Biaxial (+/-)
Optic Sign Biaxial +, Biaxial -
Luster Pearly, greasy, dull.
Polish Luster Vitreous.
Fracture Luster Vitreous, pearly.
Specific Gravity 2.55-2.75
Enhancements none
Transparency Transparent to translucent.

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
by International Gem Society