mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

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

Identified June 2, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed from the crystallization of silica-rich hydrothermal fluids in veins or as a primary constituent of igneous rocks like granite. The milky appearance is caused by tiny fluid inclusions of gas or liquid trapped during crystal growth.

Uses & applications

Used as an abrasive in sandpaper, in glassmaking, as a gemstone in jewelry, and for decorative landscaping. Also used in the manufacturing of electronics and solar panels due to its high silica content.

Geological facts

Milky quartz is one of the most common mineral varieties on Earth. The 'milkiness' is actually millions of microscopic bubbles that formed when the rock was liquid.

Field identification & locations

Identify by its hardness (it will scratch glass), lack of cleavage, and distinctive waxy-to-glassy luster. It is found globally, particularly in mountainous regions and riverbeds.