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Earth of fire

Actualité volcanique, Article de fond sur étude de volcan, tectonique, récits et photos de voyage

Wah Wah mountains are home to a treasure : the red beryl , also called red emerald .

Very rare, it is only found in three places in the world: Wah Wah mountains and the Thomas Range, in Utah , and the Black Range in New Mexico.

Utah Wah-Wah - Exceptional cluster of gorgeous Red Beryl cr
    Crystals of red beryl on a matrix of rhyolite / Wah Wah mountains - Ferris mineral collection

Red beryl was described for the first time in 1904. The largest concentration of red beryl gem quality was discovered in 1958 by Lamar Hodges during an uranium exploration .

The price for a top quality can go up to $ 10,000 per carat. Red beryl is often confused with Pezzottaite or raspberry beryl , a stone found in Madagascaret in Afghanistan. They are distinguished by the index of refraction.
 beryl scovil cornell - A 1.19-carat cut gem alongside its
            Red Beryl - A carved stone 1.19 carats versus a crystal of 1,7 cm . - Wah Wah mountains

cristaux de béryl var. béryl rouge, rhyolite - Violet Cla
Beryl - 14 mm pink -violet crystal on a rhyolite matrix - Violet claims / Wah Wah mountains - photo géry Parent

Formation of red beryl :

While beryls are ordinarily found in pegmatites and certain metamorphic rocks, red beryl occurs only in topaz -bearing rhyolites .

When the lava begins to cool, shrinkage cracks are formed , creating a loophole for high-temperature gas, rich in beryllium. Oxidized surface waters begin to interfere in the cracks and mix with gas charged in beryllium. These gases react with the surface water , silica, alkali feldspar, and  iron and manganese oxides of the lava to form delicate red beryl crystals, which grow at a temperature between 650 and 300°C. Associated minerals are quartz, topaz, spessartine , pseudobrookite , bixbyite and hematite.

Wah Wah mts. -Summitpost
                       Wah Wah mountains - Summitpost Photo

In the Thomas Range / Utah, the crystals are between 2 and 10 mm long and 4-6 thick, they are found in the Topaz Mountain Rhyolite issued there 6-7 Ma ago.

In the Wah Wah mountains ,the elongated crystals are larger than 15 mm long, the largest crystal measuring 14 x 34 mm. They are found in the rhyolite of the Blawn formation, issued there 18-20 million years ago .

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