metamorphic

Quartz-rich metamorphic rock, likely quartzite

Quartzite (mostly microcrystalline quartz, SiO₂)

AI-generated identification · may be incorrect

Hardness about 7 Mohs; pale gray-white with rusty weathering, vitreous to sugary luster, and massive granular texture. Lacks obvious cleavage and is typically very dense and resistant to scratching.

Identified September 5, 2026More metamorphic →

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Physical properties

Hardness about 7 Mohs; pale gray-white with rusty weathering, vitreous to sugary luster, and massive granular texture. Lacks obvious cleavage and is typically very dense and resistant to scratching.

Formation & geological history

Formed when quartz-rich sandstone recrystallized under metamorphic heat and pressure, commonly during mountain building; its exact geological age cannot be determined from the image. The irregular surface may reflect natural weathering or abrasion.

Uses & applications

Used as crushed stone, road aggregate, building stone, countertops, and landscaping; attractive pieces may be collected but are generally not jewelry-grade.

Geological facts

Quartzite commonly breaks across grains rather than around them, producing a rough, splintery fracture. Iron-oxide staining can create tan, orange, or reddish patches.

Field identification & locations

Field tests include scratching glass, observing abundant interlocking quartz grains, and checking that dilute acid produces no fizz; identification is uncertain without a fresh surface or hardness test. Common in metamorphic mountain belts worldwide.