mineral

Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White, cloudy, or translucent beige; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White, cloudy, or translucent beige
Luster: Vitreous to greasy

Identified June 21, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: White, cloudy, or translucent beige; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal pulses, pegmatites, and as a primary mineral in igneous rocks like granite. Milky quartz specifically contains tiny fluid inclusions trapped during crystal growth.

Uses & applications

Used in glass making, abrasive materials, precision electronics (due to piezoelectricity), and as ornamental stone or landscaping rock.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by millions of microscopic bubbles of gas or liquid trapped during its formation.

Field identification & locations

Identify by its hardness (it will scratch glass and steel), lack of cleavage, and waxy/vitreous luster. Commonly found in veins and as pebbles in stream beds globally.