mineral

Milky Quartz

Silicon Dioxide (SiO2)

Hardness: 7 (Mohs scale); Color: Opaque white to cream/tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 (Mohs scale)
Color: Opaque white to cream/tan
Luster: Vitreous to greasy

Identified May 17, 2026More mineral →

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Physical properties

Hardness: 7 (Mohs scale); Color: Opaque white to cream/tan; Luster: Vitreous to greasy; Crystal Structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Forms in hydrothermal veins or as a primary constituent in igneous rocks like granite. It is extremely common and found in geological formations across all ages due to its chemical stability.

Uses & applications

Used as a gemstone in jewelry (cabochons), as an abrasive, in the production of glass and silicon, and as a popular specimen for collectors.

Geological facts

Milky quartz is the most common variety of crystalline quartz. Its cloudy appearance is caused by tiny fluid or gas inclusions trapped during crystal growth.

Field identification & locations

Identify in the field by its hardness (scratches glass), waxy/greasy luster on broken surfaces, and lack of cleavage. Commonly found in riverbeds and mountainous terrain.