mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

Hardness: 7 on Mohs scale; Color: Colorless to white/translucent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Hardness: 7 on Mohs scale
Color: Colorless to white/translucent
Luster: Vitreous (glassy)

Identified June 22, 2026More mineral →

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Physical properties

Hardness: 7 on Mohs scale; Color: Colorless to white/translucent; Luster: Vitreous (glassy); Crystal Structure: Hexagonal; Cleavage: None (conchoidal fracture); Specific Gravity: 2.65

Formation & geological history

Formed by the deposition of silica-rich hydrothermal fluids within cavities (vugs) in volcanic or sedimentary rocks. Over millions of years, crystals grow inward toward the center of the cavity.

Uses & applications

Primarily used for desktop decoration, crystal healing, educational specimens, and lower-end jewelry. Industrial quartz is used in electronics and glass manufacturing.

Geological facts

The word geode comes from the Greek word 'Geoides' which means earth-like. Unlike solid rocks, geodes are hollow, allowing crystals to reach their perfect geometric shapes inside.

Field identification & locations

Identify in the field by looking for rounded, lumpy nodules that feel lighter than they look. Found commonly in Brazil, Uruguay, Mexico, and the United States (notably Iowa and Utah).