Quartz Geode Fragment
Silicon Dioxide (SiO2)
Rock Type: mineral

Physical Properties
Hardness: 7 on Mohs scale; Color: White to translucent exterior with dark crystalline interior; Luster: Vitreous to dull; Crystal structure: Trigonal (hexagonal); Cleavage: None (conchoidal fracture); Specific gravity: 2.65
Formation & Geological History
Formed as secondary mineralization in cavities (vugs) within volcanic or sedimentary rocks. Silica-rich hydrothermal fluids precipitate crystals over thousands of years.
Uses & Applications
Commonly used for educational purposes, small collectibles, ornamental stone, and as metaphysical 'healing' stones.
Geological Facts
Geodes are essentially 'frozen' bubbles in rock. While the outside looks like an ordinary stone, the interior can contain spectacular crystal formations like druzy quartz, amethyst, or chalcedony.
Field Identification & Locations
Identify by looking for a hollow or crystal-lined cavity within a round or nodular rinded rock. Commonly found in desert regions, stream beds, or areas with ancient volcanic activity.
Identified on: 4/26/2026
Mode: Standard