metamorphic

Gray quartz-rich stone (possibly quartzite)

Quartzite, composed primarily of quartz (SiO₂); identification is uncertain from the image

AI-generated identification · may be incorrect

Small, angular gray specimen with a dull to slightly glassy surface and fracture faces. Quartz is Mohs 7; quartzite is typically hard and lacks obvious cleavage, but hardness and composition cannot be confirmed visually.

Identified October 4, 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 depends on the source rock and regional geology.

Uses & applications

Quartzite is used as aggregate, building and paving stone, and sometimes decorative stone; this small piece has little apparent commercial value.

Geological facts

Quartzite can resemble quartz-rich vein rock or other gray silicate rocks, so a photo alone cannot establish the identification.

Field identification & locations

Check whether it scratches glass and whether fresh breaks show interlocking quartz grains; local geology and a fresh surface can help distinguish quartzite from alternatives.