mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 on the Mohs scale; Color: Opaque white to creamy tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on the Mohs scale
Color: Opaque white to creamy tan
Luster: Vitreous to greasy

Identified February 28, 2026More mineral →

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Physical properties

Hardness: 7 on the Mohs scale; Color: Opaque white to creamy tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (Conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Formed from hydrothermal veins or gas pockets in igneous rocks. While the mineral itself can be any age, it is commonly found in Proterozoic and Paleozoic formations. The white color is caused by tiny bubbles of gas or liquid trapped during crystal growth.

Uses & applications

Used in industry for glassmaking, abrasives, and electronics (due to piezoelectric properties). In jewelry, it is used for beads and cabochons. Common in landscaping and aggregate for construction.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Historically, it was used by many indigenous cultures for tool making (lithic reduction) because of its sharp edges when fractured.

Field identification & locations

Identify by its ability to scratch glass (hardness 7) and its lack of clear cleavage planes. It is ubiquitous globally, commonly found in riverbeds, mountains, and as garden stones. Collectors look for pieces with interesting inclusions or associations with other minerals.