mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness of 7 on the Mohs scale, vitreous to greasy luster, white to translucent pale greenish-white color, trigonal crystal system, conchoidal fracture, no cleavage, specific gravity of 2.65.

Identified July 25, 2026More mineral →

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Physical properties

Hardness of 7 on the Mohs scale, vitreous to greasy luster, white to translucent pale greenish-white color, trigonal crystal system, conchoidal fracture, no cleavage, specific gravity of 2.65.

Formation & geological history

Forms in a wide range of geological environments, most commonly in hydrothermally formed veins and pegmatites as silica-rich fluids cool and crystallize.

Uses & applications

Used in glassmaking, ceramics, electronics, as abrasive material, and widely collected as mineral specimens or tumbled gemstones.

Geological facts

The milky or cloudy appearance is caused by tiny microscopic fluid inclusions trapped during the crystal's growth millions of years ago.

Field identification & locations

Identified by its hardness (scratches glass, cannot be scratched by steel), glassy/greasy lustre, lack of cleavage, and translucent cloudy appearance. Extremely common worldwide in riverbeds, beach gravels, and igneous rock formations.