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Bixbite



Bixbite

General
CategoryMineral (cyclosilicate)
Chemical formulaBe3(AlMn)2Si6O18
Identification
ColorOrange-red to red to purple-red
Crystal habitElongate or tabular first order prisms.
Crystal systemHexagonal
CleavageBasal, seldom visible
FractureConchoidal
Mohs Scale hardness7.5 - 8.0
LusterVitreous
Refractive index1.567-1.580
PleochroismPurple-red/orange-red to red
StreakWhite
Specific gravity2.66-2.70

Bixbite (also known as red beryl, red emerald, or scarlet emerald) is a red variety of beryl (emerald), Be3(Al,Mn)2(SiO3)6. It was named after the Utah mineral collector Maynard Bixby, who first discovered it at Topaz Cove in the Thomas Range of Juab County, Utah [1]. Bixbite should not be confused with the similarly named bixbyite. Bixbite 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

Additional recommended knowledge

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 bixbite is very rare, and the largest faceted gemstones are less than three carats (600 mg) in size.

See also

References

  • Mindat
  1. ^ Red Emerald History (2007-11-21). Retrieved on 2007-11-21.
  2. ^ Red Emerald History (2007-11-21). Retrieved on 2007-11-21.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Bixbite". A list of authors is available in Wikipedia.
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