Mineral | Zoisite |
---|---|
Chemistry | Ca2Al3(SiO4)3(OH) |
Color | Violetish Blue - Blue |
Refractive Index | 1.691 - 1.700 |
Birefringence | 0.008 - 0.013 |
Specific Gravity | 3.35 |
Mohs Hardness | 6.0 - 7.0 |
Tanzanite is a captivating gemstone known for its unique color-changing properties and remarkable beauty. Here's a comprehensive overview of Tanzanite, covering its attributes, value, sources, properties, colors, and care
Mineral | Zoisite |
---|---|
Chemistry | Ca2Al3(SiO4)3(OH) |
Color | Violetish Blue - Blue |
Refractive Index | 1.691 - 1.700 |
Birefringence | 0.008 - 0.013 |
Specific Gravity | 3.35 |
Mohs Hardness | 6.0 - 7.0 |
Tanzanite was discovered in 1967 at the base of Mount Kilimanjaro in Tanzania, which gave the gemstone its name. Natural Tanzanite has a reddish-brown color and achieves its beautiful blue to violet hue through heat treatment. The value of Tanzanite is determined by factors such as color and clarity. Rich blue varieties are the most sought-after and valuable.
The blue to violet color of Tanzanite is its most prized characteristic. Natural blue Tanzanite is rare, and most stones achieve their color through controlled heat treatment, typically between 500-600 degrees Celsius for about 30 minutes.
The primary source of Tanzanite is Tanzania, specifically the Merelani Hills in the Lelatema Mountains. Other related gemstones from Tanzania include Anyolite, which features deep green crystals colored by chromium and often includes Ruby crystals, and Thulite, which is found in various locations worldwide.
Tanzanite is predominantly found in Tanzania, and all gemstones labeled as Tanzanite are sourced from this region. Most rich blue Tanzanites have undergone a stable heat treatment process to enhance their color.
Tanzanite has a hardness ranging from 6 to 7 on the Mohs scale but is relatively brittle and can cleave easily, making it more suitable for occasional rather than daily wear. Cleaning Tanzanite is best done with a soft brush, mild detergent, and warm water.