metamorphic
Quartzite
Quartzite, composed predominantly of quartz (SiO₂)
AI-generated identification · may be incorrectWhite to cream, granular and slightly sparkly, with a vitreous-to-dull luster; quartz has Mohs hardness 7 and trigonal crystal structure. The specimen’s grains appear fused, but exact identification needs testing.
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Physical properties
White to cream, granular and slightly sparkly, with a vitreous-to-dull luster; quartz has Mohs hardness 7 and trigonal crystal structure. The specimen’s grains appear fused, but exact identification needs testing.
Formation & geological history
Forms when quartz-rich sandstone is recrystallized under heat and pressure, typically during regional metamorphism; its age depends on the source sandstone and metamorphic event.
Uses & applications
Used as dimension stone, landscaping aggregate, and occasionally for decorative objects; this unworked piece has little jewelry value.
Geological facts
Quartzite is so quartz-rich that it can fracture through grains rather than around them, unlike many sandstones.
Field identification & locations
Look for a hard, quartz-rich rock that resists scratching by a steel knife and lacks the easy grain separation of sandstone. Quartzite occurs in metamorphic belts worldwide; this image alone cannot establish the exact locality or rule out another quartz-rich rock.
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