Gemstones - Precious Gems
Tanzanite
Coined as a trade name by Tiffany and Company in 1969, Tanzanite has been accepted as the the common name for heat treated zoisite.
The lovely blue and purple gemstone is native to Tanzania.
But be careful with the gem, especially in rings, as the softness (6.5) means Tanzanite can be damaged more easily than some harder gems
This image shows the trichroic properties of Tanzanite, various hues when illuminated along different axes.
courtesy Tanzanite0ne.com
Properties of Tanzanite
- Crystal System - Orthorhombic
- Hardness - 6 to 7
- Specific Gravity - 3.35
- Refraction - Double
- Refractive Index - 1.757 to 1.779
- Dispersion -
- Birefringence -
- Wearability - Fair to Good
- Special Care - Avoid impact
Care of Tanzanite
Recommendations from Tanzanite One
"Tanzanite has a similar hardness to an emerald, but is less brittle. In order to preserve its beauty, simple precautions should be taken, such as avoiding wearing tanzanite during activities that inflict excessive wear and tear. Tanzanite is ideally suited for occasion wear in dress rings, earrings and necklaces.
"Like all precious gemstones, tanzanite should be treated with care to preseve its beauty and value. Ultrasonic cleaning and abrasive cleaning solutions should be avoided. Tanzanite should be cleaned using a small, soft brush and warm, slightly soapy water. Gently clean the upper and underside of the tanzanite, and dry carefully with a soft, clean cloth.
"Tanzanite should not be exposed to sudden extremes of temperature and should be stored in a protective pouch or box separately from other jewelry. When jewelry is being altered or repaired, the tanzanite should be removed from its setting beforehand."