mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white with iron oxide (rust) staining; 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 with iron oxide (rust) staining
Luster: Vitreous to greasy

Identified June 29, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes when silica-rich fluids cool and crystallize in earth's crustal fractures. The milky appearance is caused by millions of tiny trapped fluid inclusions or gas bubbles during crystal growth.

Uses & applications

Used in glass manufacturing, as a source for silicon metal for electronics, in construction as aggregate, and as landscaping stone. Low-grade specimens are often used for metaphysical or decorative purposes.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Pure quartz is clear; the white 'milkiness' of this specimen indicates it formed in a high-pressure hydrothermal environment.

Field identification & locations

Identify by its hardness (it will scratch glass), lack of cleavage, and characteristic waxy or glassy luster. Commonly found in riverbeds, mountains, and as 'float' stones in soil. It is a common indicator of mineralizing veins nearby.