Milky Quartz

Physical Properties

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

Formation & Geological History

Forms through hydrothermal activity within veins in igneous, metamorphic, and sedimentary environments. The white color is caused by tiny inclusions of gas or liquid trapped during crystal growth.

Uses & Applications

Used in glassmaking, abrasives, as a flux in metallurgy, and as a semi-precious gemstone. High-purity quartz is vital for the electronics and semiconductor industry.

Geological Facts

Milky quartz is the most common variety of crystalline quartz. Its opacity is due to minute fluid inclusions of gas or liquid that were trapped during the crystal's formation.

Field Identification & Locations

Identify by its white color, inability to be scratched by steel, and lack of cleavage. It is found globally in mountains, riverbeds, and as vein material in many rock types.

Identified on: 5/2/2026

Mode: Standard