metamorphic

Quartz-rich rock, likely milky quartz or quartzite

Quartz (SiO₂), possibly quartzite with minor feldspar and iron-oxide staining

AI-generated identification · may be incorrect

White to gray, translucent grains with a glassy to dull luster; quartz hardness is Mohs 7, with no cleavage and conchoidal fracture. The granular, fused texture suggests quartzite, though the photograph cannot distinguish it confidently from massive milky quartz.

Identified September 7, 2026More metamorphic →

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Physical properties

Formation & geological history

Quartzite forms when quartz-rich sandstone is metamorphosed under heat and pressure, commonly during regional mountain building; its age depends on the original sandstone and metamorphic event. Massive quartz can instead form in hydrothermal veins, filling fractures in older rocks.

Uses & applications

Used as aggregate, decorative stone, silica feedstock, and occasionally as a lapidary material; attractive translucent pieces may be polished, but this specimen appears ordinary.

Geological facts

Quartz is one of Earth’s most abundant minerals and commonly develops milky coloration from microscopic fluid inclusions, fractures, or impurities.

Field identification & locations

Look for very high scratch resistance, absence of cleavage, and grains that remain interlocked rather than crumbling like sandstone; common in metamorphic belts and quartz veins worldwide. A streak test should be white, and a steel knife should not scratch it.