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Natural Iolite Cabochons

Refraction Index: 1.522 - 1.578
Hardness:  7 - 7.5  
Species: Cordierite
Specific Gravity:   2.53 - 2.78
Treatment: None
Care: Wash with soapy water. Avoid harsh detergents. Never clean ultrasonically or steam clean.

Iolite cabochons are a beautiful transparent blue violet gemstone.  Iolites name comes from the Greek word for violet. It has also been called "water-sapphire".  Iolite is sometimes used as an inexpensive substitute for sapphire.  

Metal Clay, safe to fire at some temperatures.
Test results; Silver 1200F-1HR-OK, Silver 1475F-1HR a little darker, Silver 1650F-2HR Metallic, Bronze 1525F-2HR OK, Copper 1778F-30min color change to lavender.