mineral

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Typically white to translucent with a glassy luster and irregular conchoidal fracture; hardness 7 Mohs, no cleavage, hexagonal crystal structure, and specific gravity about 2.65. The blurred specimen appears massive and milky rather than showing distinct crystal faces.

Identified August 16, 2026More mineral →

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Physical properties

Formation & geological history

Forms when silica-rich fluids crystallize in veins, cavities, and igneous or metamorphic rocks; its age depends on the host deposit and may range from ancient Precambrian to recent. Common sources include Brazil, Madagascar, the United States, and worldwide vein systems.

Uses & applications

Used for glass, ceramics, engineered stone, abrasives, electronics, and decorative specimens; attractive translucent pieces may be used in carvings or inexpensive jewelry.

Geological facts

Milky appearance results from microscopic fluid inclusions, fractures, or inclusions scattering light. Quartz is one of Earth’s most abundant minerals and is resistant to weathering.

Field identification & locations

Field clues include scratching ordinary glass, a white streak, lack of cleavage, and curved fracture surfaces; it should not be confused with calcite, which is softer and cleaves readily. Common in quartz veins, granite pegmatites, and metamorphic rocks.