mineral

Quartz Geode Fragment

Silicon Dioxide (SiO2)

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

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

Identified April 11, 2026More mineral →

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Physical properties

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

Formation & geological history

Formed in cavities (vesicles) within igneous rocks or sedimentary nodules where silica-rich groundwater precipitates crystals over long periods. These can range from millions to hundreds of millions of years old.

Uses & applications

Used in jewelry (beads/pendants), home decor, metaphysical collecting, and as a source of high-purity silica for electronics and glass manufacturing.

Geological facts

Quartz is the most abundant and varied mineral on Earth's surface. Geodes are unique because they are 'rock fossils' of gas bubbles or hollow cavities that existed in the earth long ago.

Field identification & locations

Identify by its hardness (will scratch glass), glassy luster, and typical bumpy outer rind (the host rock). Commonly found in dry, volcanic areas or limestone-rich regions.