sedimentary
Sandstone Concretion
Sedimentary Concretion (Quartz arenite cemented by iron oxides)
AI-generated identification · may be incorrectHardness of 6-7 on Mohs scale due to quartz content. Displays reddish-brown to tan coloration with a dull, earthy luster and granular texture.
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Physical properties
Hardness of 6-7 on Mohs scale due to quartz content. Displays reddish-brown to tan coloration with a dull, earthy luster and granular texture.
Formation & geological history
Formed in sedimentary layers by the precipitation of mineral cement around a nucleus, often occurring in sandstone formations.
Uses & applications
Collected by rockhounds and used as decorative landscape stones or geological display specimens.
Geological facts
These spherical or discoidal masses often weather out of softer surrounding rock, earning them local nicknames like Kansas worry stones or Indian paint pots.
Field identification & locations
Easily identified by its distinct rounded, nodular form and greater hardness compared to the enclosing host rock. Commonly found in sedimentary basins throughout the Midwest.
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