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Where is Tanzanite found?

Zoisite (blue variety)

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Tanzanite occurs in specific geological environments. Knowing where to look, and in what kind of rock, is the difference between going home empty-handed and finding a great specimen.

Where to find Tanzanite

Merelani Hills, Manyara Region, Tanzania

The only commercially significant source of tanzanite in the world. Found in a geologically unique area within the Neoproterozoic Mozambique Belt.

Collecting tips

  1. Geological Context. Tanzanite is found exclusively in specific metamorphic rock formations within the Merelani Hills. Prospecting would require detailed geological mapping and understanding of the local structural and metamorphic history.
  2. Associated Minerals. Often found in association with graphite, diopside, tremolite, grossular garnet, and quartz within the host rock.
  3. Color Variation. Raw tanzanite can appear brownish. The characteristic blue-violet color is often developed or enhanced through heat treatment. Natural blue tanzanite is extremely rare.

Quick Check

Color:
Blue to violet-blue, strong trichroism (blue, violet, burgundy)
Luster:
Vitreous
Streak:
White

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