Tanzanite (Zoisite)
“Discovered in 1967, found nowhere else”
Mineral
Tanzanite is the blue-violet gem variety of the mineral zoisite, found at only one location on Earth — a small area near Mount Kilimanjaro in Tanzania. Its striking trichroism means it shows different colors (blue, violet, and burgundy) depending on the angle of view and lighting.
Composition
calcium aluminum silicate hydroxide (Ca₂Al₃(SiO₄)(Si₂O₇)O(OH))
Where Found
Merelani Hills, Manyara Region (Tanzania — the only known source worldwide)
Mohs Hardness
6-7
Fun Fact
Tanzanite was named by Tiffany & Co. in 1968 because they felt its scientific name 'blue zoisite' sounded too much like 'blue suicide' — not ideal for marketing luxury jewelry.
Test Your Knowledge
Why is tanzanite found at only one location on the entire planet?
Photo Attribution
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