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Opal

The specimen below contains all of the colors of blues, golds, oranges, whites and clear with excellent translucency.


  • Blue Mountain Range,
    Morrow County, Oregon
  • Price: $2350


 

The deposit at Opal Butte in Morrow County has been known since the late 1800's. It was of interest only to hobbyists until recently because people believed most of the opal was unstable. Stability can be a problem with the opal, crazing can occur when stresses are created from shrinkage due to water loss. The opals are found in rhyolite geodes (thundereggs) in a perlite that has altered to a pastel colored clay. The geodes that contain gem-quality opal are only about 10% of the total geodes mined and only about 1% of the geodes contain gem-quality opal with play of color. The remaining geodes contain agate, quartz crystals, or common opal. The geodes vary greatly in size, from a few centimeters in diameter to over a meter.

 

 

 

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