Milky Quartz

Physical Properties

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

Formation & Geological History

Forms in hydrothermal veins or pegmatites from cooling silica-rich fluids. It is found in igneous, metamorphic, and sedimentary environments globally, often dating back hundreds of millions of years.

Uses & Applications

Used in glassmaking, abrasives, electronics (as oscillators), construction aggregate, and as decorative garden stone or lapidary material.

Geological Facts

The milky appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's cooling process. It is the most common variety of crystalline quartz on Earth.

Field Identification & Locations

Identify by its ability to scratch glass, its lack of cleavage, and common occurrence in riverbeds or mountain trails. It is a key indicator for potential gold mineralization in quartz veins.

Identified on: 5/3/2026

Mode: Standard