gemstone
Tanzanite
Zoisite (Ca2Al3(SiO4)(Si2O7)O(OH))
AI-generated identification · may be incorrectHardness of 6-7 on the Mohs scale, vivid violet-blue to blue-purple color, vitreous luster, and orthorhombic crystal system with distinct cleavage.
Identified More gemstone →
Explore Tanzanite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness of 6-7 on the Mohs scale, vivid violet-blue to blue-purple color, vitreous luster, and orthorhombic crystal system with distinct cleavage.
Formation & geological history
Formed in metamorphic environments within complex orogenic belts approximately 585 million years ago during the Neoproterozoic era.
Uses & applications
Primarily used as a high-value precious gemstone in fine jewelry and as a prized collector specimen.
Geological facts
Found exclusively in the Merelani Hills of Northern Tanzania near Mount Kilimanjaro, making it one of the rarest gemstones on Earth.
Field identification & locations
Easily identified by its unique trichroism, showing distinct blue, violet, and brownish-red colors depending on the viewing angle.
More like this
Other gemstone specimens
Ammolite
Ammolite (Biogenic Aragonite with trace elements; fossils of Placenticeras meeki and Placenticeras intercalare)
mineral
Gemstone Ring
N/A - Set piece of jewelry, likely Amethyst or Garnet with Diamond or CZ
gemstone
Topaz
Al2SiO4(F,OH)2
mineral
Amber
Succinite (Organic Gemstone)
mineral
Diamond and Gold Jewelry
Carbon (Diamond) / Au (Gold)
gemstone
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
sedimentary