Opal
Access point 6, Coober Pedy, South Australia state, Australia
IMA approved name
Opal pseudomorph after bivalvia
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Width of the right specimen: 10 mm. Opal pseudomorph after shell fossil. The translucent white part is opal replacing bivalvia fossil. The red- and blue-based rainbow color is the play of color of noble opal.
Recovered from the weathered part of shale deposited in a shallow marine environment and subjected to diagenesis.
Other localities
- Hagidaira Mine (Bedded Mn, Noble Opal)
- Hosaka (Rhyolite, Nodule)
- Sukayu hot spring (Hot spring, Massive)
- Opal Quest Mine (Shale, replacing Bivalvia)
- Old Timers Mine (Shale, replacing Bivalvia)