mineral

Milky quartz

Quartz (silicon dioxide, SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to translucent, vitreous-to-waxy luster, and irregular conchoidal fracture. It has a trigonal crystal structure but commonly occurs as massive, non-crystalline-looking material; brown lines are likely iron-oxide staining or fractures.

Identified August 24, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich hydrothermal fluids or igneous rocks crystallize, often in veins cutting surrounding rock. Quartz is widespread from Precambrian to modern geological settings, so an exact age cannot be determined from the image.

Uses & applications

Used for glass, ceramics, engineered stone, abrasives, electronics, and ornamental specimens; attractive translucent pieces may be tumbled or carved.

Geological facts

Milky appearance results from microscopic fluid inclusions, fractures, or scattered impurities. It can resemble white calcite, but quartz is substantially harder and does not readily cleave.

Field identification & locations

Common in quartz veins, pegmatites, granitic terrains, and stream gravels worldwide. A steel file should not scratch it; vinegar usually produces no reaction, helping distinguish it from calcite.