opal: Quick Facts

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opal, raw, from Coober Pedy, Austl.

Old Timers Mine, Coober Pedy, Austl.

Coober Pedy opal mining

Life in an underground opal-mining town

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Topics

siliceous sinter white opal black opal fire opal hydrophane October silica mineral gemstone birthstone garnet jade quartz topaz turquoise tourmaline jasper jadeite zircon amethyst

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silica mineral: Opal

Basalt sample returned by Apollo 15, from near a long sinous lunar valley called Hadley Rille. Measured at 3.3 years old.

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