Milky Quartz

Physical Properties

Hardness: 7 on the Mohs scale. Color: White to cloudy. Luster: Vitreous (glassy) to greasy. Crystal Structure: Hexagonal/Trigonal. Cleavage: Poor/Conchoidal fracture. Specific Gravity: 2.65.

Formation & Geological History

Formed from the crystallization of silica-rich hydrothermal solutions or cooling magma. The white 'milky' appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in veins or as pebbles in sedimentary deposits.

Uses & Applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction as an aggregate, and landscaping. High-quality specimens are used in jewelry or as pocket stones.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz. Its white color is often likened to the appearance of milk or snow.

Field Identification & Locations

Identify in the field by its hardness (it will scratch glass), its lack of cleavage (it breaks in curved, shell-like patterns), and its translucent white color. It is commonly found in gravel pits, mountain streams, and rocky outcrops.

Identified on: 4/22/2026

Mode: Standard