Mineral

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale. Color: Opaque white (milky) to translucent gray. Luster: Vitreous to greasy. Crystal Structure: Hexagonal (trigonal). Cleavage: None (conchoidal fracture). Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Opaque white (milky) to translucent gray
Luster: Vitreous to greasy

Identified January 25, 2026More mineral →

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Physical properties

Formation & geological history

Formed from hydrothermal solutions depositing silica in fractures of pre-existing rock. Often found in metamorphic or igneous environments, occurring across a wide range of geological ages from Precambrian to recent.

Uses & applications

Used as a source of high-purity silica for glassmaking, electronics (silicon chips), and as a common decorative stone or construction aggregate. Collectors value larger crystal points.

Geological facts

Milky quartz gets its cloudy appearance from microscopic inclusions of gas or liquid trapped during crystal growth. It is one of the most abundant and chemically stable minerals on Earth's crust.

Field identification & locations

Identify in the field by its ability to scratch glass and lack of cleavage (it breaks in irregular, curved shards). Look for it in riverbeds or protruding from outcrops of darker host rock. Commonly found worldwide.

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

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Mineral/Rock

Banded Gneiss (River Rock/Pebble)

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