Milky Quartz with Limonite

Physical Properties

Hardness: 7 on Mohs scale; Color: Cloudy white to tan with brownish-yellow staining; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (Trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65.

Formation & Geological History

Formed from hydrothermal solutions or cooling magma in veins. This specific piece likely weathered out of a quartz vein where iron-rich fluids left limonite (rust) deposits. Quartz is found in almost all geological ages.

Uses & Applications

Milky quartz is used as an abrasive, in the production of glass and ceramics, and as a landscaping stone. It is a common collector's item for beginners.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. The 'milky' appearance is caused by tiny fluid inclusions of gas or liquid trapped during the crystal's growth.

Field Identification & Locations

Identify by its ability to scratch glass, its lack of cleavage (it breaks like glass), and the presence of rusty stains. It is ubiquitously found in riverbeds, mountain trails, and construction gravel.

Identified on: 4/20/2026

Mode: Standard