Wednesday, 22 March 2017

Red Beryl

Red beryl is an extremely rare variety of beryl that receives its red color from trace amounts of manganese. World-wide, crystals suitable for cutting gems have been found in one location only, the Ruby-Violet claims in the Wah Wah Mountains of Beaver County, Utah. The Utah Geological Survey estimated that one crystal of red beryl is found for every 150,000 gem-quality diamonds.

Red beryl is extremely rare because its formation requires a unique geochemical environment. First, the element beryllium must be present in large enough amounts to form minerals. Second, dissolved manganese must also be present at the same time and location. Third, the correct geochemical conditions must be present for beryllium, manganese, aluminum, silicon, and oxygen to crystallize into red beryl. Fractures and cavities must also be available to serve as a space for the crystals to grow.

At the Ruby-Violet mine, the topaz rhyolite is a lava flow that erupted from volcanic vents about 18 to 20 million years ago. As the lava flow cooled, fractures and cavities developed in the rock. These openings allowed superheated beryllium-rich water and gases to enter the formation. These were released from a magma chamber that was degassing below.

At the same time, surface water was entering fractures above and moving downwards. It carried oxygen, manganese, aluminum, and silicon leached from the rocks above.
Superheated water and gases from below encountered cool waters from above, which produced a change in geochemical conditions that triggered mineral crystallization.

Red beryl rough is rarely larger than one carat and most faceted red beryls are 0.2 carat or less. Most specimens of red beryl from Ruby-Violet have a rich saturated red color. This allows tiny faceted stones to exhibit a vivid red color.
Lab-created red beryl was first produced in Russia by the hydrothermal process in the mid-1990s. As of January 2016, the lab was no longer producing red beryl. Lab-created red beryl has the same composition and physical properties as natural red beryl but gemologists familiar with the materials are able to distinguish lab-created from natural.

The name "red emerald" is sometimes used when referring to red beryl. This name is a misnomer because emerald, by definition, is green.