mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to cloudy
Luster: Vitreous to greasy

Identified June 14, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to cloudy; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed in hydrothermal veins or pegmatites from silicon-rich fluids cooling deep within the Earth's crust across various geologic ages. The milky appearance is caused by millions of tiny fluid and gas inclusions trapped during crystal growth.

Uses & applications

Used in the manufacturing of glass and ceramics, as an abrasive, in electronics (due to piezoelectric properties), and as inexpensive landscaping stone or decorative rock.

Geological facts

Milky Quartz is one of the most common varieties of crystalline quartz on Earth. While it appears white to the naked eye, under a microscope it contains countless microscopic bubbles of water or carbon dioxide.

Field identification & locations

Identified by its white color, inability to be scratched by a steel knife, and lacks cleavage planes. It is globally abundant and often found in mountain ranges, riverbeds, and as quartz veins cutting through other rock types.