mineral

Milky Quartz Vein with Iron Staining

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent with yellowish-brown iron oxide staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal (hexagonal prisms); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Luster: Vitreous to greasy

Identified April 22, 2026More mineral →

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Physical properties

Formation & geological history

Formed through hydrothermal processes where silica-rich fluids precipitate in rock fractures. Often associated with pegmatites and metamorphic belts. Age can range from Proterozoic to Cenozoic depending on location.

Uses & applications

Used as a source for silicon in electronics, an abrasive in sandblasting, decorative landscape stone, and occasionally crushed for road base or glass manufacturing.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Massive white quartz is often called 'bull quartz' in the mining industry and can sometimes be an indicator for gold mineralization in hydrothermal veins.

Field identification & locations

Identify by its ability to scratch glass (hardness 7), lack of cleavage, and waxy/crystalline appearance. It is found globally in almost all geological environments, especially in mountain ranges and riverbeds.

Other mineral specimens

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Sandstone (with potential mineral staining/concretions)

Arenite (SiO2 based)

sedimentary

Schist

Metamorphic

Epidote

Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)

metamorphic

Nephrite Jade

Nephrite

Mineral/Rock

Banded Gneiss (River Rock/Pebble)

Gneiss (specifically a banded variety often found as a river rock)

Metamorphic Rock

Green Apatite on Albite

Fluorapatite [Ca5(PO4)3F] on Albite [Na(AlSi3O8)]

mineral