
Holtite Value, Price, and Jewelry Information
This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
Optics:a= 1.743-1.746; β= 1.756-1.759; γ= 1.758-1.761.
Biaxial (-), 2V= 49-55°.
Occurrence: Alluvial tin deposit near Greenoushes, Western Australia, associated with cassiterite.
Comments: This mineral was first noted in 1937 but was not described in detail until 1971. It has not yet been seen as a gem, but the high hardness would allow it be worn with no risk of scratching. Holtite is now considered to be a variety of dumortierite. The mineral comes from the one locality, and a cut stone would have to be considered a great rarity.
Name: After Harold E. Holt, prime minister of Australia from 1966 to 1967.
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