12 tanzanite facts
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| Tanzanite |
- Tanzanite is the blue/purple variety of the mineral zoisite which was discovered in the Meralani (Merelani) Hills of Northern Tanzania in 1967, near the city of Arusha.
- Tanzanite in its rough state is usually a reddish brown color. It requires artificial heat treatment to 600 °C in a gemological oven to bring out the blue violet of the stone.
- Its rich purple and blue often has a depth comparable to the finest sapphire.
- Tanzanite is a rare gem. It is found mostly in the foothills of Mount Kilimanjaro.
- When tanzanite is found in the ground, the brown color dominates. However, with gentle heating, the cutter can watch the blue color bloom and deepen in the stone.
- The mineral is named after Tanzania, the country where it was discovered.
- Tanzanite is more delicate than other gemstones and should not be set in a ring that will be worn during strenuous activity.
- The world's largest faceted tanzanite is 737.81 carats. One of the most famous large tanzanites (242 carats) is the "Queen of Kilimanjaro".
- Never clean tanzanite in an ultrasonic cleaner.
- Because tanzanite is relatively soft, it is not usually set in necklaces and earrings, so the tiara is truly a rarity.
- Mohs scale hardness: 6.5
- A lab-created simulant of tanzanite is called tanzanique.
