mineral

Bull Quartz

Quartz (Silicon Dioxide, SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to tan with iron staining; Luster: Vitreous to greasy; Crystal Structure: Trigonal (often massive in this form); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Milky white to tan with iron staining
Luster: Vitreous to greasy

Identified May 23, 2026More mineral →

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Physical properties

Formation & geological history

Formed from silica-rich hydrothermal fluids cooling in veins and fissures within the Earth's crust, or as a major constituent of igneous rocks like granite.

Uses & applications

Commonly used as a source of high-purity silica for glassmaking, electronics, and silicon metal production; also used as a decorative landscaping stone or construction aggregate.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. Massive white quartz is often called 'Bull Quartz' by miners because it is tough to work with and frequently indicates the absence of valuable metals like gold, though it can sometimes serve as a host rock.

Field identification & locations

Identify in the field by its hardness (will scratch glass easily), lack of cleavage, and characteristic milky white color with brownish iron oxide stains. Found globally in almost all geological environments.