mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on the Mohs scale
Color: White to translucent
Luster: Vitreous to greasy

Identified March 17, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: White to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed through the cooling and crystallization of silica-rich hydrothermal fluids or magma. This specimen appears to be from a quartz vein. The geological age can range from millions to over a billion years depending on the local bedrock.

Uses & applications

Used in the production of glass, ceramics, and electronics (silicon chips). Historically and currently used as decorative stone, in jewelry as 'snow quartz', and in construction as gravel or aggregate.

Geological facts

Milky quartz gets its white, cloudy appearance from tiny microscopic inclusions of gas and/or liquid trapped during crystal growth. It is the most common variety of crystalline quartz found on the Earth's surface.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage (it breaks into irregular, curved shards), and its resistance to weathering. Found globally in mountains, riverbeds, and coastal sands.