mineral

Milky Quartz

Silicon Dioxide (SiO2)

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

Hardness: 7 (Mohs scale)
Color: White to translucent creamy-white
Luster: Vitreous to greasy

Identified March 8, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed through the cooling of silica-rich hydrothermal fluids or the crystallization of magma in igneous veins. It is most commonly found in pegmatites and hydrothermal veins and can be billions of years old.

Uses & applications

Used in glassmaking, construction as aggregate, electronics (piezoelectric properties), and as decorative stones or tumbled gemstones in entry-level collecting.

Geological facts

The 'milky' appearance is caused by tiny inclusions of gas and/or liquid trapped during crystal growth. It is one of the most common and widely distributed minerals on Earth's crust.

Field identification & locations

Identify by its ability to scratch glass and lack of cleavage (it breaks in irregular curves). Commonly found in riverbeds, mountains, and gravel pits globally. Collectors should look for semi-transparent edges and a waxy surface texture.