mineral

Quartz Crystal Cluster (with Selenite Satin Spar)

Silicon Dioxide (SiO2)

AI-generated identification · may be incorrect

Hardness: 7 on Mohs scale; Color: Milky white to colorless; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Hardness: 7 on Mohs scale
Color: Milky white to colorless
Luster: Vitreous (glassy)

Identified July 4, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Milky white to colorless; Luster: Vitreous (glassy); Crystal Structure: Hexagonal (trigonal); Cleavage: None (conchoidal fracture); Specific Gravity: 2.65.

Formation & geological history

Forms through hydrothermal activity where silica-rich hot water cools in crustal fractures or cavities. The specimens shown are likely from the Phanerozoic eon, found globally in metamorphic and igneous environments.

Uses & applications

Used extensively in electronics for its piezoelectric properties, in glassmaking, as abrasives, and highly valued by collectors and for metaphysical jewelry.

Geological facts

Quartz is the second most abundant mineral in Earth's continental crust. The second piece pictured above is a 'Satin Spar' variety of Selenite (Gypsum).

Field identification & locations

Identified by its hexagonal crystal habit and its ability to scratch glass (hardness 7). Common locations include Brazil, USA (Arkansas), and Madagascar.