Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: White to creamy/milky; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/conchoidal fracture; Specific Gravity: 2.65

Formation & Geological History

Forms in hydrothermal veins, pegmatites, and as a primary constituent in igneous rocks like granite. The milky color is caused by microscopic inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used as a source of high-purity silica for glassmaking, abrasives, electronics (piezoelectric properties), and as inexpensive jewelry or landscaping stones.

Geological Facts

Milky quartz is the most common variety of crystalline quartz. It can sometimes contain trace amounts of gold within its vein structures, making it a target for prospectors.

Field Identification & Locations

Identify by its hardness (will scratch glass), white opaque color, and lack of visible cleavage. Commonly found in riverbeds, mountains, and near quartz veins globally.

Identified on: 5/19/2026

Mode: Standard