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Found today in a creek in Indiana, has a geode look and the broken edge shows red opaque facades.

enter image description here

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closed as off-topic by Universal_learner, uhoh, Peter Jansson, Jan Doggen, arkaia Jul 13 at 15:55

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  • "Please review our rock identification guidelines to provide the missing information so that your question is both answerable and useful to new users." – Universal_learner, uhoh, Peter Jansson, Jan Doggen, arkaia
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Your rock appears to be quartz var. chalcedony (jasper) with the interior being quartz pseudomorph after another mineral probably calcite or aragonite. I've seen a number of quartz pseudomorph after calcite from Indiana over the years but I do not have a good reference for Indiana pseudomorphs.

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Gary's answer is valid but I might suggest that Cinnabar is also a possibility. To give a definitive opinion we really need to know how hard the material is.

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