mineral

Bull Quartz (Milky Quartz)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Opaque white to cream with brownish iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal (often massive in boulders); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Opaque white to cream with brownish iron staining
Luster: Vitreous to greasy

Identified April 9, 2026More mineral →

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Physical properties

Formation & geological history

Formed from hydrothermal solutions cooling in veins and fractures within host rocks or as large masses in pegmatites. This specimen likely weathered out of a larger quartz vein over millions of years.

Uses & applications

Used in landscaping (decorative garden stones), crushed for industrial silicon production, glass manufacturing, and as an abrasive.

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's surface.

Field identification & locations

Identify by its 'milky' white appearance and superior hardness (it will easily scratch glass and steel). Commonly found in areas with metamorphic or igneous activity; look for heavy, white outcrops in hilly terrain.