Tanzanite
A variety of Zoisite
What is Tanzanite?
Tanzanite is a relatively rare gemstone that is a deep-blue variety of zoisite. This color can be enhanced with extreme heating and is usually done so for retail purposes. This gemstone is named after its one and only area of occurrence, the Mererani Hills in Tanzania. Tanzanite is regarded as the birthstone for December and for 24th-year anniversaries.
Uses & Applications
Because of its exceptional strength and clarity, as well as expert marketing by Tiffany and Co. Tanzanite is now the world's second most popular blue gemstone. It is most commonly faceted and set into jewelry pieces such as earrings, rings, and necklaces, although raw stones are becoming popular in these settings as well.
Healing Properties
Tanzanite is believed to act as a "reset button," especially after a trauma or interruption in daily life. Many believe it promotes relaxation and improves physical ailments when worn. It is said to have the power to release a person's creative energy that might otherwise be blocked, allowing the individual to focus and regain intention with their goals.
Optical Properties
- Refractive Index
- 1.685-1.707
- Birefringence
- 0.006-0.013
- Pleochroism
- Violet/purple stones - strong trichroism: strong blue, purple, greenish to brownish yellow; Blue stones - strong: strong blue, purple, greenish-yellow
- Optical Character
- Biaxial positive
- Dispersion
- 0.03
Discover Values
This stone excels in beauty, collection value.
Tanzanite Market Value Calculator
Estimate the market value of Tanzanite using size, quality, and finish. This preview calculator is for quick context and is not a formal appraisal.
Tanzanite Localities Map
See where Tanzanite is found with a localities map, collecting zones, and geology context. Generate a sample map preview below.
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Quick Facts
Physical Properties
- Color
- Blue to blue-violet, brown, pale grey, red
- Hardness (Mohs)
- 6 - 7
- Density
- 3.35 g/cm³
- Streak
- White, colorless
- Luster
- Vitreous
- Crystal System
- Orthorhombic
Chemical Properties
- Chemical Formula
- {Ca2}{Al3}(Si2O7)(SiO4)O(OH)
- Elements
- Al, Ca, H, O, Si
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