Milky Quartz with Iron Inclusions

Silicon Dioxide (SiO2)

Rock Type: mineral

Milky Quartz with Iron Inclusions

Physical Properties

Hardness: 7 on Mohs scale; Color: Opaque white to light gray with brown/yellow iron staining; Luster: Vitreous to greasy; Crystal structure: Hexagonal; Cleavage: None/Conchoidal fracture; Specific gravity: 2.65

Formation & Geological History

Formed through the cooling of silica-rich hydrothermal fluids in veins or pegmatites. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used in the production of glass, ceramics, and as an abrasive. Also used in construction aggregate and as decorative landscaping stones.

Geological Facts

Milky quartz is the most common variety of crystalline quartz. Historically, it has been used for various stone tools due to its hardness and chip patterns.

Field Identification & Locations

Identify in the field by its white color, inability to be scratched by a steel knife, and lack of cleavage (breaks like glass). Commonly found in mountain ranges and riverbeds worldwide.

Identified on: 5/4/2026

Mode: Standard