metamorphic
Likely quartz-rich stone (possibly quartzite)
Quartzite, composed predominantly of quartz (SiO₂)
AI-generated identification · may be incorrectThe specimen is gray-brown, rough, and weathered, with a granular or sparkly surface; hardness is about 7 Mohs if quartzite. Crystal structure is trigonal for quartz, but the image alone does not establish the rock’s identity or cleavage.
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Physical properties
The specimen is gray-brown, rough, and weathered, with a granular or sparkly surface; hardness is about 7 Mohs if quartzite. Crystal structure is trigonal for quartz, but the image alone does not establish the rock’s identity or cleavage.
Formation & geological history
Quartzite forms when quartz sandstone is recrystallized by heat and pressure during metamorphism; its age depends on the source rock and metamorphic event.
Uses & applications
Quartzite is used as crushed stone, building and paving material, and sometimes as decorative stone; this small rough piece is mainly suitable for collecting.
Geological facts
Quartzite can resemble ordinary quartz-rich sandstone, but metamorphic recrystallization fuses its grains into a hard, durable rock.
Field identification & locations
Look for a hard, quartz-rich surface and grains that resist scratching; quartzite occurs in metamorphic terrains worldwide. The specimen’s exact identification cannot be confirmed from the photo alone.
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