Rare gemstones: Red Beryl

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Photo by Pala International

Red beryl is a red variety of beryl. It was first described in 1904 for an occurrence, its type locality, at Maynard’s Claim (Pismire Knolls), Thomas Range, Juab County, Utah. The old synonym “bixbite” is deprecated from the CIBJO, because of the risk of confusion with the mineral bixbyite (also named after the mineralogist Maynard Bixby). The dark red color is attributed to Mn3+ ions.
Red beryl is very rare and has only been reported from a handful of locations including: Wah Wah Mountains, Beaver County, Utah; Paramount Canyon and Round Mountain, Sierra County, New Mexico; and 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.

During the late Cretaceous (100 – 65 mya) the younger ranges of the Rocky Mountains were created, and deep fractures appeared which reached deep into the crust. In course of volcanic activities (appr. 20 mya), five or more layers of volcanic topaz rhyolite lava flows covered areas in todays Utah. Then hot fluorine and beryllium-rich gases and vapors, rising through shrinkage cracks of the cooled lava, met groundwater resources near the surface. The water evaporated and left behind niches or miarolitic cavities and porous areas in which the remaining steam could react under low pressure and high temperatures (300° – 650° C) with the rising mineral-rich gases so that red beryl crystals could grow.

Red beryl is the rarest member of the beryl family. Unfortunately there is just a small production of gemmy crystals because of their rarity. Most faceted stones are under 1 ct, and most of them are more or less included or appear as opaque “bubble gum” quality. Nevertheless “bubble gum” colored red beryls are offered, sometimes in good quality.
Faceted, clean stones with a “stop-light” color over 1 ct are extremely rare and priced as such, reaching sometimes over $10,000 / ct (in 2007).
The largest, yet recovered red beryl crystal was 1.4 x 3.4 cm (54 ct). The largest faceted stone (not clear) weighs 8.0 ct. Nevertheless the usual size of good, faceted red beryl is only 0.15 ct!
K. Hyslop, CEO of Gemstone Mining Inc.: “There is only one red emerald for every 150,000 diamonds, 12,000 – 15,000 emeralds, and 7,000 – 8,000 rubies. Only one woman in 3 million can own a 0.80 ct or larger red emerald. These goods are really fit for royalty, only one woman in 50 million could own a large red emerald necklace.” (Source: “Red Emerald or Red Beryl” in The Gemstone Forecaster, Vol. 18 No.3)

Red beryl has been known to be confused with pezzottaite, also known as raspberry beryl or “raspberyl”, a gemstone that has been found in Madagascar and now Afghanistan – although cut gems of the two varieties can be distinguished from their difference in refractive index.
While gem beryls are ordinarily found in pegmatites and certain metamorphic stones, red beryl occurs in topaz-bearing rhyolites. It is formed by crystallizing under low pressure and high temperature from a pneumatolitic phase along fractures or within near-surface miarolitic cavities of the rhyolite. Associated minerals include bixbyite, quartz, orthoclase, topaz, spessartine, pseudobrookite and hematite.

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Physical Properties of Red Beryl
Mohs Hardness: 7.5 to 8

Specific Gravity: 2.63 to 2.72

Refractive Index: 1.560 to 1.576

Optical Character: Uniaxial/-

Birefringence: 0.005 to 0.009

Colour (General): Red, violet-red
Causes of Colour: Red, Mn3+ in octahedral coordination.

Fluorescence (General): Inert

Crystal System: Hexagonal
Inclusions in Red Beryl: “Fingerprints” made by numerous fluid inclusions

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