Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: Opaque white to cream, often with iron staining (yellowish); Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & Geological History

Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. The milky appearance is caused by tiny liquid or gas inclusions trapped during crystal growth.

Uses & Applications

Used as a source of silica for glassmaking and silicon chips, an abrasive in sandpaper, in construction as aggregate, and as a popular decorative stone for gardens or entry-level mineral specimens.

Geological Facts

Milky Quartz is the most common variety of crystalline quartz. While it lacks the transparency of clear quartz, it can sometimes contain inclusions of gold or pyrite in certain geological environments.

Field Identification & Locations

Identify in the field by its white color, lack of cleavage, glass-like fracture, and its ability to easily scratch glass. It is virtually ubiquitous in mountain ranges and riverbeds globally.

Identified on: 4/20/2026

Mode: Standard