Dave Babulski, Ed.D.
("Tips and Trips", Volume XXXIV/Twelve December 2005, page 7.)
Greetings everyone. This month we will be investigating micromounts of the mineral beryl. Chemically, beryl is a beryllium aluminum silicate. There are several varieties exhibiting minor chemical impurities which cause specific wavelengths of light to be absorbed resulting in a very strong color to the mineral. Listed below are the most common varieties of beryl and their colors:
Pale Blue: Aquamarine
Red: Bixbite (Also called red beryl)
The red variety of beryl is the only one that occurs as micro-crystals. The topaz bearing rhyolite of the Wah Wah Mountains in Utah is the most common location for red beryl. Although pricy, micromounts of red beryl are readily available from mineral dealers. There is something almost mystical about the deep red color of red beryl, particularly when strongly illuminated under the microscope. The other colored varieties of beryl are much more difficult to obtain as micromounts. I have found some very small gemmy crystals of morganite, the pink variety of beryl in the topaz bearing rhyolite at Topaz Mountain, Utah. These are rare and you need to break down a lot of material to find one. Aquamarine is the most readily available variety of beryl, but still difficult to find in gemmy crystals. Much of the aquamarine specimens I have seen have been pale blue opaque crystals. By far the real prizes for micromounters are gemmy crystals of emerald, the deep green variety of beryl. Occasionally you will find a mineral dealer with good “in matrix” thumbnail specimens of emerald crystals. These can be broken down to make some very fine micromounts. However, be prepared to pay a princely sum for the specimens. Specimens from the Columbian emerald mines afford the best specimens. Shown above is a photomicrograph of a gemmy micromount of emerald from the Muzo Mine in Columbia. (Photographed with Kodak 400 color print film at 50X with white LED illumination - 4 second exposure.) Although beryl represents a challenge to the micromount collector, when you find a fine specimen it adds immeasurably to your collection. At the upcoming mineral shows, I will be prowling the mineral dealer tables on the look out for some fine beryl specimens for micromounts. See you there. Until then may all your skies by blue and may all your vugs be crystal filled.
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