metamorphic

Quartzite

Quartzite, composed predominantly of quartz (SiO₂)

AI-generated identification · may be incorrect

A compact, rounded, pinkish-tan specimen with a granular, slightly sparkly surface and no obvious cleavage. Quartz hardness is 7 Mohs; quartzite is typically hard and scratches glass, with a vitreous-to-sugary luster and interlocking quartz grains.

Identified October 13, 2026More metamorphic →

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Physical properties

Formation & geological history

Forms when quartz-rich sandstone is recrystallized by heat and pressure, commonly during regional metamorphism; its age depends on the source sandstone and metamorphic event.

Uses & applications

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

Geological facts

Iron oxides commonly impart pink, red, or brown colors. Unlike sandstone, quartzite’s grains are tightly fused, so it tends to fracture through grains rather than crumble around them.

Field identification & locations

Look for a hard, quartz-rich rock with a sugary sparkle and no easy grain separation; common in metamorphic mountain belts worldwide. The photo suggests quartzite, though visual identification alone is not definitive.