mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: Milky white to light gray
Luster: Vitreous to greasy

Identified May 25, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in veins or as a late-stage crystallization in igneous pegmatites. It is found in a wide variety of geological environments ranging from Precambrian to recent ages.

Uses & applications

Used in the manufacturing of optical and electronic equipment, glassmaking, as an abrasive, and in landscaping. Polished stones like this are popular in jewelry and for decorative or holistic collecting.

Geological facts

The milky appearance is caused by tiny invisible fluid inclusions of gas or liquid trapped during crystal growth. It is the most common variety of crystalline quartz.

Field identification & locations

Identify by its characteristic white cloudiness, lack of cleavage, and ability to scratch glass. Commonly found in riverbeds, mountain ranges, and pegmatite deposits worldwide.