mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: White, grayish-white, to opaque milky appearance. Luster: Vitreous to greasy. Crystal System: Trigonal. Cleavage: None (conchoidal fracture).

Hardness: 7 on Mohs scale
Color: White, grayish-white, to opaque milky appearance
Luster: Vitreous to greasy

Identified July 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale. Color: White, grayish-white, to opaque milky appearance. Luster: Vitreous to greasy. Crystal System: Trigonal. Cleavage: None (conchoidal fracture).

Formation & geological history

Forms in igneous, metamorphic, and sedimentary environments, frequently occurring in hydrothermal veins and pegmatites where fluid inclusions (gas or liquid bubbles trapped during crystallization) cause the distinctive milky opacity.

Uses & applications

Used in glassmaking, ceramics, electronics (as a source of silicon), abrasives, landscaping, and gemstone carving or lapidary collection.

Geological facts

Milky quartz is one of the most common quartz varieties on Earth. Its cloudy white appearance is due to millions of microscopic fluid inclusions trapped during the mineral's growth.

Field identification & locations

Identify by its hardness (scratches glass, cannot be scratched by steel), glassy to waxy luster, lack of cleavage, and translucent to opaque white color. Found globally in stream beds, gravel pits, veins, and rocky outcrops.