Milky Quartz

Quartz (Silicon Dioxide - SiO2)

Rock Type: mineral

Milky Quartz

Physical Properties

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

Formation & Geological History

Formed through the crystallization of magma or from hydrothermal veins. Milky quartz specifically gets its appearance from tiny fluid 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 a landscaping stone. Low-grade specimens are common for beginner collectors.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is the most common variety of quartz found in nature.

Field Identification & Locations

Identify in the field by its inability to be scratched by a steel knife and its lack of cleavage planes. It is found globally in igneous, metamorphic, and sedimentary environments.

Identified on: 4/26/2026

Mode: Standard