mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white
Luster: Vitreous (glassy) to greasy

Identified March 25, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Opaque white; Luster: Vitreous (glassy) to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms from the cooling of silica-rich hydrothermal fluids in veins or as a constituent of igneous rocks like granite. Its white color is caused by microscopic fluid inclusions of gas and/or liquid trapped during crystal growth.

Uses & applications

Used in the glass and ceramic industries, as an abrasive, in construction as aggregate, and in landscaping. It is also a source of silicon for electronics and popular for decorative carvings and beginner mineral collections.

Geological facts

Milky Quartz is the most common variety of crystalline quartz. Historically, it was used by ancient civilizations for stone tools due to its hardness and predictable fracture patterns.

Field identification & locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its characteristic 'greasy' feel on weathered surfaces. Commonly found in riverbeds, pegmatites, and mountainous regions worldwide.