mineral

Quartz (Milky/Smoky Crystal fragment)

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Translucent white to light gray; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); SG: 2.65.

Hardness: 7 on Mohs scale
Color: Translucent white to light gray
Luster: Vitreous (glassy)

Identified May 28, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Translucent white to light gray; Luster: Vitreous (glassy); Crystal structure: Trigonal/Hexagonal; Cleavage: None (conchoidal fracture); SG: 2.65.

Formation & geological history

Formed through the cooling of silica-rich magma or from hydrothermal veins. Quartz is found in almost all geological environments and across all geological ages, common in igneous, metamorphic, and sedimentary settings.

Uses & applications

Extensively used in glass making, electronics (piezoelectric properties), abrasives, construction sand, and as a gemstone/healing crystal for collectors.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. It is highly resistant to both chemical and physical weathering, which is why it often remains as grains in sand.

Field identification & locations

Identify by its hardness (will scratch glass), glassy luster, and lack of cleavage (it breaks in curved patterns). Look for it in riverbeds, granite outcrops, and volcanic regions worldwide.

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