Quartz Geode (partially formed)

Silicon Dioxide (SiO2)

Rock Type: mineral

Quartz Geode (partially formed)

Physical Properties

Hardness: 7 (Mohs scale), Color: Smoky brown to translucent white, Luster: Vitreous to dull (external shell), Crystal Structure: Trigonal, Cleavage: None/Conchoidal fracture, Specific Gravity: 2.65

Formation & Geological History

Formed when mineral-rich hydrothermal fluids seep into cavities in volcanic or sedimentary rocks. Over time, crystals grow inward. Typically occurs in vesicles of basalt or limestone cavities.

Uses & Applications

Commonly used for geological study, home decor, meditation/metaphysical purposes, and as entry-level mineral specimens for collectors.

Geological Facts

Geodes can range from the size of a marble to several meters across. This specimen shows a 'vug,' which is a small cavity within a rock lined with crystals.

Field Identification & Locations

Identify by looking for a bumpy, roundish exterior that is lighter than expected for its size. In the field, shaking a geode may sometimes reveal loose crystals rattling inside. Commonly found in desert regions or near volcanic ash deposits.

Identified on: 4/20/2026

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