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Precious opal (Spencer Opal Mine, Spencer, Idaho, USA) |
Geyser Opal from Spencer Idaho U.S.A Spenser Opal was deposited in volcanic rocks about 4 million years ago by geysers.
The Opal is Hydrothermally deposited inside hollow geodes in successive layers making Spencer Opal ideal for triplets as the thin layers of extremely high quality precious opal are very transparent with great color intensity.
Opal doublets, often used in jewelry, are thin slices of precious opal glued onto a matrix material. Such gems are considerably cheaper than solid opals, yet provide the same play of color. Opal doublets are sometimes coated with a thin layer or dome of clear Quartz to make them more resistant to scratches (opal is a relatively soft gem). These are known as triplets.
To make a triplet the opal is ground perfectly flat parallel to the fire layer until the intense fire shows completely across the surface. Then a flat piece of black Basinite or obsidian is epoxied to the flat fire layer.
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Precious opal (Spencer Opal Mine, Spencer, Idaho, USA). Photo:James St. John |
Spencer Opal Mine, Spencer, Idaho The opals are contained in a rhyolite and obsidian flow with abundant gas pockets. Hydrothermal fluids from hot spring activity filled the pockets with common and precious opal. The cost for digging is $15.00 for adults (13 and up) $10.00 for kids (4-12).
Address: 27 Opal Ave, Spencer, ID 83446
Geyser Opal from Spencer Idaho U.S.A Spenser Opal was deposited in volcanic rocks about 4 million years ago by geysers.
See also:Part I: Top Spots For Gem Hunting In The US
Part II: Top Spots For Gem Hunting In The US
The Only Diamond Mine In the World Where You Can Be the Miner
Where to Find Opals in Oregon?