minerals

Quartz / Quartzite

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to translucent
Luster: Vitreous to greasy

Identified July 6, 2026More minerals →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to translucent; Luster: Vitreous to greasy; Crystal Structure: Hexagonal (trigonal); Cleavage: None/Conchoidal fracture; Specific Gravity: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or through hydrothermal activity. This specific specimen appears to be a weathered river pebble or part of a vein. Quartz is found in rocks of all geological ages.

Uses & applications

Commonly used in construction (as sand/aggregate), glass making, electronics (due to piezoelectric properties), and as a gemstone (tumbled or carved).

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to chemical and physical weathering, which is why it is so commonly found as rounded pebbles in rivers and on beaches.

Field identification & locations

Identify in the field by its hardness (it will scratch glass) and its lack of cleavage. Look for the characteristic 'waxy' or glass-like luster on fresh breaks. It is ubiquitous globally.