mineral

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Hardness: 7 on Mohs scale
Color: Opaque white to yellowish-tan
Luster: Vitreous to greasy

Identified July 5, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids in veins or pegmatites. The white color is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used in construction as aggregate, as a source of silica for glass making, and in decorative landscaping or jewelry (tumbled stones).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature.

Field identification & locations

Identify in the field by its inability to be scratched by a steel knife (hardness 7) and its lack of cleavage. Often found as rounded pebbles in stream beds or as veins in larger rock outcrops.