mineral

White Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

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

Hardness: 7 on Mohs scale
Color: White to opaque
Luster: Vitreous (glassy) to greasy

Identified February 17, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich magma or through hydrothermal activity in veins. It is found in a vast range of geological environments and ages, common in igneous, metamorphic, and sedimentary settings.

Uses & applications

Used in glassmaking, abrasives, foundry sand, electronics (piezoelectric properties), and widely as a lapidary material for tumbled stones, beads, and decorative carvings.

Geological facts

Milky quartz gets its cloudy white appearance from tiny fluid inclusions of gas or liquid trapped during the crystal's growth. It is the most common variety of crystalline quartz on Earth.

Field identification & locations

Identify in the field by its hardness (it will scratch glass), lack of cleavage, and common occurrence in veins. Found globally, especially in mountain ranges and stream beds as pebbles.

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