mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 Mohs; Color: White to off-white, opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Hardness: 7 Mohs
Color: White to off-white, opaque
Luster: Vitreous to greasy

Identified July 9, 2026More mineral →

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Physical properties

Hardness: 7 Mohs; Color: White to off-white, opaque; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: Indistinct/Conchoidal fracture; Specific Gravity: 2.65

Formation & geological history

Formed through the crystallization of silica-rich hydrothermal solutions in veins or during the cooling of igneous magmas. It is found in many geological environments ranging from igneous to metamorphic terrains.

Uses & applications

Used as an abrasive, in glass making, as a gemstone (tumbled or cabochon), in electronics (piezoelectric properties), and as a landscape stone.

Geological facts

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

Field identification & locations

Identify by its ability to scratch glass (Hardness 7), its opaque white appearance, and lack of cleavage planes. It is ubiquitous in riverbeds and mountainous regions globally.