mineral
Tiffany Stone
Bertrandite (Be4Si2O7(OH)2) mixed with Fluorite (CaF2), Opal, and Chalcedony
Hardness: 4 to 7 (variable); Color: White, purple, violet, cream, with black veins; Luster: Vitreous to waxy; Crystal Structure: Amorphous/Microcrystalline; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.1 - 2.65
- Hardness
- 4 to 7 (variable)
- Color
- White, purple, violet, cream, with black veins
- Luster
- Vitreous to waxy
Identified More mineral →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 4 to 7 (variable); Color: White, purple, violet, cream, with black veins; Luster: Vitreous to waxy; Crystal Structure: Amorphous/Microcrystalline; Cleavage: None/Conchoidal fracture; Specific Gravity: 2.1 - 2.65
Formation & geological history
Formed in volcanic ash or tuff deposits through hydrothermal activity where fluorine-rich fluids interacted with beryllium-bearing minerals, primarily in the Spor Mountain region of Utah during the Tertiary period.
Uses & applications
Used primarily in lapidary arts as a semi-precious gemstone for cabochons and carvings; also historically crushed for its beryllium content used in aerospace and automotive alloys.
Geological facts
Also known as 'Ice Cream Opalite' or 'Bertrandite'. It is considered one of the rarest specimens in the world because it is almost exclusively found at the Brush Wellman beryllium mine in Utah, which is closed to public collecting.
Field identification & locations
Identify by its distinctive 'swirling' or 'fractured' purple and white patterns. In the field, look for nodules or heavy mineralization in rhyolitic tuff. Most specimens reach the market through old stockpiles from the Topaz-Spor mountain region.
More like this
Other mineral specimens
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Nephrite Jade
Nephrite
Mineral/Rock
Banded Gneiss (River Rock/Pebble)
Gneiss (specifically a banded variety often found as a river rock)
Metamorphic Rock
![Green Apatite on Albite (Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]) — mineral](https://media.rockidentification.com/2391a63f-fb20-47d5-af9a-2035851eb32e-thumbnail.jpg)
Green Apatite on Albite
Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]
mineral
Epidote
Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)
mineral