Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: White to opaque; 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 magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used in glass manufacturing, as an abrasive, in electronics (due to piezoelectric properties), and as decorative landscaping stone or ornamental carvings.

Geological Facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many ancient cultures to create stone tools and arrowheads through knapping.

Field Identification & Locations

Identify by its hardness (scratches glass), lack of cleavage, and white opaque color. It is commonly found in gravel beds, mountain ranges, and as vein material in many different rock types worldwide.

Identified on: 5/9/2026

Mode: Standard