sedimentary
Geode
Silicon dioxide and chalcedony nodule
AI-generated identification · may be incorrectHardness 7 on Mohs scale, typically grey exterior with a hollow or crystal-lined interior, vitreous luster, microcrystalline quartz structure.
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Physical properties
Hardness 7 on Mohs scale, typically grey exterior with a hollow or crystal-lined interior, vitreous luster, microcrystalline quartz structure.
Formation & geological history
Formed in sedimentary or volcanic rock cavities through mineral-rich groundwater deposition over millions of years.
Uses & applications
Used primarily in lapidary arts, decorative items, mineral collections, and metaphysical practices.
Geological facts
Geodes often contain sparkling quartz or amethyst crystals hidden completely inside an unassuming exterior shell.
Field identification & locations
Identify by its spherical shape, bumpy exterior texture, and relatively lightweight feel due to a hollow core.
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