"Pinfire opal" is a name used for opal that has pinpoints of fire throughout the stone. The opal on the left is a pinfire opal cut from material mined at Coober Pedy, Australia. The stone on the right is a pinfire opal from the Constellation Mine in Spencer, Idaho. It is 6 millimeters by 4 millimeters in size. The video below illustrates the "play of color" in a pinfire opal.
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The opal on the left is a pinfire opal cut from material mined at Coober Pedy, Australia. The stone on the right is a pinfire opal from the Constellation Mine in Spencer, Idaho. It is 6 millimeters by 4 millimeters in size.