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need help identifying these rocks, not sure if obsidian, onyx, or tourmaline, or something else?

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asked Apr 26, 2016 by Mariekrc (120 points)
edited Apr 29, 2016 by Mariekrc

2 Answers

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Looks like obsidian to me. Where did you find it?
answered Apr 27, 2016 by Weasel (58,980 points)
It was found in Mason City Iowa, in a construction site that has been digging. I have a bunch more pieces. Some shinier than others, with different shapes, and also some lava rock.
Please post a few pics of your interesting rocks.
I have posted more pictures of the stones let me know what you think! Thank you.
0 votes
Could also be goethite or hematite - the pictures are not clear. The white nodule looks like calcite. Markiekrc - any way you can test the streak? That could really help with identifying.
answered Jul 24, 2016 by hershel (52,800 points)

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