Milky Quartz

Physical Properties

Hardness: 7 on Mohs scale; Color: Milky white to tan (due to iron staining); Luster: Vitreous to greasy; Crystal Structure: Trigonal (often massive in samples like this); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & Geological History

Formed from the cooling of silica-rich hydrothermal fluids in veins or as a late-stage mineral in igneous pegmatites. It can be found in rocks of almost any geological age, from Precambrian to Cenozoic.

Uses & Applications

Used as an abrasive, in the production of glass and ceramics, and as a source of silicon for electronics. Lower quality massive quartz is used in construction aggregate and landscaping.

Geological Facts

The milky white appearance is caused by millions of tiny microscopic bubbles of gas and liquid trapped during the crystal's growth. It is one of the most abundant minerals in the Earth's crust.

Field Identification & Locations

Identify in the field by its ability to scratch glass, its lack of cleavage, and its characteristic waxy or glassy luster. Often found as white 'veins' cutting through other rock types like schist or granite.

Identified on: 4/23/2026

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