mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: White to translucent gray with tan/yellow staining; Luster: Vitreous to greasy; Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific gravity: 2.65

Hardness: 7 (Mohs scale)
Color: White to translucent gray with tan/yellow staining
Luster: Vitreous to greasy

Identified April 20, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes, cooling of magma in pegmatites, or metamorphism. It can be found in vein deposits or as masses. Quartz is incredibly stable and persists as other rocks weather away.

Uses & applications

Used in glassmaking, abrasives, jewelry (cabochons), electronics (oscillators), and construction as aggregate. Large specimens are popular for garden landscaping and crystal collecting.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (will scratch glass and steel), white/cloudy appearance, and lack of cleavage. Commonly found in riverbeds, mountains, and as 'veins' in granite outcrops.