Milky Quartz

Physical Properties

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

Formation & Geological History

Formed through the crystallization of silica-rich hydrothermal solutions in veins or as a primary constituent in igneous, metamorphic, and sedimentary rocks. The white color is caused by microscopic fluid inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used as a source of silicon, in glassmaking, as an abrasive, in construction as aggregate, and frequently in landscaping or as a common collector specimen.

Geological Facts

Milky quartz is the most common variety of crystalline quartz. While it lacks the clarity of rock crystal, it is physically the same mineral and can contain trace amounts of gold in certain hydrothermal vein environments.

Field Identification & Locations

Identify by its ability to scratch glass (high hardness), its white 'waxy' appearance, and the lack of cleavage planes. It is found globally and is extremely resistant to weathering, often appearing as water-worn pebbles in stream beds.

Identified on: 4/20/2026

Mode: Standard