metamorphic

Quartz-rich stone (likely quartzite)

Quartzite, composed predominantly of quartz (SiO₂)

AI-generated identification · may be incorrect

Tan-gray, rough and granular with a dull to slightly glassy luster; quartz has Mohs hardness 7 and no cleavage. The photo does not show enough detail to confirm the identification or measure specific gravity.

Identified September 23, 2026More metamorphic →

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Physical properties

Formation & geological history

Quartzite forms when quartz-rich sandstone is recrystallized by heat and pressure during metamorphism; its age and source cannot be determined from the image.

Uses & applications

Quartzite is used as construction and decorative stone, aggregate, and sometimes as a collectible specimen; this small rough fragment has no evident jewelry-grade features.

Geological facts

Quartzite can resemble quartz-rich sandstone, but recrystallized grains typically interlock rather than separating easily.

Field identification & locations

The small, irregular tan-gray fragment appears quartz-rich, but a close-up or hardness test would be needed to distinguish quartzite from other common rocks. Quartzite occurs worldwide in metamorphic terrains.