Indonesian Opalized Wood Cabochon

Indonesian opalized wood is petrified wood in which the wood grains have been replaced by opal.  When wood is buried by volcanic ash rainwater moves silica down into the wood replacing the wood. The blue color comes from copper.

This cabochon measures 15x9x4.2mm.  The girdle height is approx. 2.0mm and has a 5 degree slope to assist in setting.  The back is polished as well.

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