Red beryl
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| Red beryl | |
|---|---|
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| General | |
| Category | Mineral (cyclosilicate) |
| Chemical formula | Be3(AlMn)2Si6O18 |
| Identification | |
| Color | Orange-red to red to purple-red |
| Crystal habit | Elongate or tabular first order prisms. |
| Crystal system | Hexagonal |
| Cleavage | Basal, seldom visible |
| Fracture | Conchoidal |
| Mohs Scale hardness | 7.5 - 8.0 |
| Luster | Vitreous |
| Refractive index | 1.567-1.580 |
| Pleochroism | Purple-red/orange-red to red |
| Streak | White |
| Specific gravity | 2.66-2.70 |
Red beryl (also known as bixbite, red emerald or scarlet emerald) is a red variety of beryl (emerald), Be3(Al,Mn)2(SiO3)6. It was named after its type locality Maynard's Claim (Pismire Knolls), Thomas Range, Juab County, Utah, USA. [1].
The old synonym bixbit is deprecated from the CIBJO, because of the risk of confusion with the mineral Bixbyite (named after the mineralogist Maynard Bixby (1853-1935)), from which it was erroneously derived. The name bixbit shouldn't be used any longer.
Red beryl is rare and has only been reported from a handful of locations including:
- Wah Wah Mountains, Beaver County, Utah
- Paramount Canyon, Sierra County, New Mexico
- Round Mountain, Sierra County, New Mexico
- Thomas Range, Juab County, Utah
The greatest concentration of gem-grade red beryl comes from the Violet Claim in the Wah Wah Mountains of mid-western Utah, discovered in 1958 by Lamar Hodges, of Fillmore, Utah, while he was prospecting for Uranium [2].
While gem beryls are ordinarily found in pegmatites and certain metamorphic rocks, Bixbite occurs in topaz-bearing rhyolites. It formed by crystallizing under low pressure and high temperature from a pneumatolitic phase along fractures or within near-surface miarolitic cavities of rhyolitic magmas. Associated minerals include bixbyite, quartz, orthoclase, topaz, spessartine garnet, pseudobrookite and hematite. The red color is thought to be from manganese substituting for aluminium in the beryl structure.
Gem-quality red beryl is very rare, and the largest faceted gemstones are less than three carats (600 mg) in size.
[edit] See also
[edit] References
- ^ MinDat - Red beryl
- ^ Red Emerald History (2007-11-21). Retrieved on 2007-11-21.
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