metamorphic

Weathered quartz-rich rock, possibly iron-stained quartz or quartzite

Quartz (SiO₂), likely in a quartzite or quartz-vein matrix with iron oxides

AI-generated identification · may be incorrect

Hardness about 7; translucent gray-brown to rusty brown, with a glassy to dull luster and irregular fracture. The granular, compact texture suggests abundant interlocking quartz grains; cleavage is absent.

Identified August 17, 2026More metamorphic →

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Physical properties

Formation & geological history

Quartzite forms when quartz-rich sandstone is recrystallized during metamorphism, while quartz veins precipitate from hot, silica-rich fluids in fractures. Its exact geological age cannot be determined from the photograph.

Uses & applications

Common quartzite is used as aggregate, road stone, building stone, and decorative rock; attractive pieces may be collected but are generally low-value.

Geological facts

The brown-red coloration likely comes from weathered iron oxides such as hematite or limonite coating or replacing parts of the quartz-rich material.

Field identification & locations

Test with a steel knife: quartz-rich material should resist scratching; glassy grains and white-to-gray quartz support the identification. Common worldwide in metamorphic belts and quartz veins.