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[MadeeMac]

I cracked open a few Geodes(and nodules) collected near Bloomington Indiana. Any ideas on what this one might be? It is metallic and fibrous.

[Bob Harman]

A typical solid Indiana geode, long ago weathered out of the surrounding limestone host rock.
The white is druzy quartz, the center cavity is not metallic, but weathering/corroding calcite.
To check, put some vinegar or, better yet, muriatic acid on it. With the acid it should fizz.

On this website go to "A mineralogical trip thru the states of the USA" Go to "Indiana" There you will see many examples of geode finds from Monroe County. BOB

[MadeeMac]

Thank you for the information!!!’