Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to greasy; Crystal Structure: Trigonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & Geological History

Formed through the cooling of silica-rich magma or from hydrothermal veins. The milky appearance is caused by tiny inclusions of gas or liquid trapped during crystal growth. They can be found in a wide variety of geological ages.

Uses & Applications

Used in glass manufacturing, electronics (due to piezoelectric properties), construction aggregates, and as decorative landscaping stone. High-purity quartz is used in solar panels.

Geological Facts

Quartz is the second most abundant mineral in Earth's continental crust. Milky quartz is often found alongside gold in hydrothermal vein deposits, leading many prospectors to use it as an indicator stone.

Field Identification & Locations

Identify in the field by its hardness (it can scratch glass), lack of cleavage, and common occurrence as rounded river pebbles or jagged vein fragments. Found globally in riverbeds, mountains, and beaches.

Identified on: 4/22/2026

Mode: Standard