mineral

Milky quartz (rough quartz fragment)

Quartz, silicon dioxide (SiO₂)

AI-generated identification · may be incorrect

Hardness 7 Mohs; white to translucent with a vitreous-to-waxy luster, no cleavage, and irregular conchoidal fracture. Hexagonal crystal structure is obscured by the massive, rounded form; the tan area may be iron-oxide staining or an inclusion.

Identified August 22, 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; specimens can range from ancient Precambrian material to geologically recent vein growth. The pictured piece may be naturally weathered or tumbled/polished, though its identity cannot be confirmed from the image alone.

Uses & applications

Used in glassmaking, ceramics, abrasives, engineered stone, and electronics; attractive translucent pieces are collected or used decoratively, but this specimen appears low-grade for jewelry.

Geological facts

Quartz is one of Earth’s most abundant minerals and commonly occurs with feldspar, mica, and calcite. Milky appearance results mainly from microscopic fluid inclusions and structural defects.

Field identification & locations

Identify by its glassy luster, lack of cleavage, hardness greater than ordinary steel, and conchoidal fracture; common worldwide, especially in hydrothermal veins and pegmatites. A streak test should be white, and glass should not scratch it.