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-red to yellow color, vitreous to greasy luster, and amorphous crystal structure with conchoidal fracture.
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Physical properties
Hardness of 5.5 to 6.5 on the Mohs scale, vibrant orange-red to yellow color, vitreous to greasy luster, and amorphous crystal structure with conchoidal fracture.
Formation & geological history
Forms in hydrothermal veins and cavities within volcanic rocks as silica-rich water deposits trapped silica gel at low temperatures.
Uses & applications
Widely used in high-end jewelry such as rings, necklaces, and earrings due to its fiery brilliance.
Geological facts
Unlike precious opal, fire opal is prized primarily for its intense body color rather than a play of color, though some specimens display both.
Field identification & locations
Identified by its distinctive warm body color, lack of cleavage, and transparent to translucent appearance. Commonly sourced from Mexico.
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