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What
gemstone is found in Utah that is rarer than diamond and more
valuable than gold?
by Carl Ege
Specimen of red beryl from the Ruby-Violet claims in the Wah Wah Mountains.
U.S. quarter for scale.
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The gemstone has several different names: red beryl, red emerald,
or bixbite. Originally, the mineral was named bixbite, but now red
beryl is the most accepted designation. Red beryl is estimated to
be worth 1,000 times more than gold and is so rare that one red
beryl crystal is found for every 150,000 diamonds.
In 1904, Maynard Bixby discovered red beryl in the Thomas Range
located in Juab County, Utah. Bixby thought it might be a new variety
of beryl, but the raspberry- red color did not correlate with any
beryl known to exist at that time (green, blue, pink, yellow, and
clear/white). W.F. Hillebrand, a geochemist from the National College
in Washington, D.C., identified the mineral as a new type of beryl
in 1905.
In 1912, Dr. A. Eppler named it bixbite in honor of its discoverer.
Laboratory analysis showed that manganese and small amounts of iron,
chromium, and calcium create the raspberry-red color of red beryl.
Like other beryl, red beryl has a hardness of 7.5 to 8.0 and its
chemical composition is Be3Al2Si6O18.
Red beryl formation began with the eruption of a topaz rhyolite
lava from volcanic vents. As the lava began to cool, shrinkage cracks
formed, creating pathways for hightemperature gases rich in beryllium
to escape. Oxidized surface water also began seeping into these
cracks and mixed with the rising beryllium gases. The gases reacted
with the surface water, silica, alkali feldspar, and ironmanganese
oxides from the lava to form red beryl crystals.
Red beryl probably grew at temperatures between 300 to 650 degrees
Celsius. Red beryl is presently found at only three locations in
the world: the Thomas Range and the Wah Wah Mountains in west-central
Utah, and the Black Range in New Mexico.
In the Thomas Range, red beryl occurs primarily as short, flat,
hexagonal crystals or more rarely as elongated, barrelshaped crystals.
The crystals are generally up to 2 10 mm long and 4
6 mm thick. Many of these crystals are too small to be faceted.
They are found in cavities and fractures within the Topaz Mountain
rhyolite that erupted approximately 6 to 7 million years ago from
volcanic vents in the area.
Small crystals can be found in an area called "the Cove,"
where they may be attached to other minerals such as topaz, bixbyite,
garnet, pseudobrookite, or hematite. Larger crystals that have been
faceted into gemstones have been found in the northwest part of
the Thomas Range near Wildhorse Springs.
The only known deposit of large, gem-quality red beryl in the world
is from the Ruby-Violet claims in the Wah Wah Mountains of Beaver
County, Utah. These are private claims and no collecting is allowed
without permission from the present claim owners.
The crystals occur primarily as elongated hexagonal crystals that
are up to 15 mm in length, and the largest crystal discovered to
date is 14 mm wide and 34 mm long. Red beryl is generally found
along large, near-vertical, northwest-trending fractures and clay-filled
seams within the rhyolite member of the Blawn Formation. The rhyolite
erupted approximately 18 to 20 million years ago from volcanic vents
in the area.
The property has periodically been worked and continues to produce
nice mineral specimens and stones suitable for faceting. Red beryl
crystals from this location that have been faceted sell for an average
of $2,000 per carat. For comparison, gold is currently worth $300
to $320 per ounce (one ounce is equal to 155 carats).
For more information regarding red beryl, contact the Natural Resources
Map & Bookstore (801) 537-3320, or toll free at 1 (888)
UTAHMAP. The bookstore has several rock and mineral publications
available for purchase that describe areas where to collect red
beryl.
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