Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Rock Type: mineral

Milky Quartz

Physical Properties

Hardness: 7 (Mohs scale). Color: White to translucent. 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 magma or through hydrothermal activity in veins. It is one of the most common minerals in the Earth's crust and can be found in a wide variety of geological ages.

Uses & Applications

Used in glassmaking, as an abrasive, in the production of silicon, and as a low-cost gemstone/decorative stone. In microelectronics, high-purity quartz is essential.

Geological Facts

The milky white color is caused by tiny inclusions of gas or liquid trapped during the mineral's formation. It's often found as 'vein quartz' filling cracks in other rock types.

Field Identification & Locations

Identify in the field by its hardness (scratches glass), lack of cleavage, and characteristic white appearance. It is ubiquitous worldwide, found in nearly every environment from mountains to beaches.

Identified on: 5/4/2026

Mode: Standard