Milky Quartz
Silicon Dioxide (SiO2)
Rock Type: mineral

Physical Properties
Hardness: 7 (Mohs scale), Color: White to cloudy translucent, Luster: Vitreous to greasy, Crystal Structure: Hexagonal (trigonal), Cleavage: Indistinct/Conchoidal fracture, Specific Gravity: 2.65
Formation & Geological History
Formed through the crystallization of silica-rich hydrothermal fluids in veins or as a primary mineral in igneous and metamorphic rocks across all geological eras.
Uses & Applications
Used in glass making, abrasive manufacturing, electronics (due to piezoelectric properties), and as decorative gravel or low-cost gemstone/jewelry elements.
Geological Facts
The milky appearance is caused by tiny inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz.
Field Identification & Locations
Identify by its hardness (scratches glass), waxy/glassy luster, and lack of cleavage. Commonly found in riverbeds, mountain veins, and as cobbles in sedimentary deposits.
Identified on: 5/3/2026
Mode: Standard