gemstone
Fire Opal
Hydrated amorphous silica (SiO2.nH2O)
AI-generated identification · may be incorrectHardness of 5.5 to 6.5 on the Mohs scale, vibrant orange to red or yellow color, vitreous to sub-resinous luster, and amorphous crystal structure.
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Physical properties
Hardness of 5.5 to 6.5 on the Mohs scale, vibrant orange to red or yellow color, vitreous to sub-resinous luster, and amorphous crystal structure.
Formation & geological history
Formed at low temperatures from silica-rich water solutions filling voids in volcanic rock, primarily in Mexico and Australia.
Uses & applications
Valued as a gemstone for use in jewelry, rings, necklaces, and collector displays.
Geological facts
Unlike typical opals, fire opals are prized for their bright body color rather than a play-of-color, though some specimens display both.
Field identification & locations
Identified by its warm, fiery translucent body color and conchoidal fracture; commonly sourced from Mexican volcanic deposits.
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