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Identity HelpConcretion with Pyrite?

13th Oct 2019 00:48 UTCSteve Federico

Dear Sirs,this is a rock found in northwest Ohio,USA at a spot with lots of glacial erratics but it might be a little closer to home than Canada.I think it is a weathered piece of a concretion with lots of pyrite.What I know:
 color:gold,rusty metallic
streak:black tested on many differant places
hardness:at least 5.5 tested in multi places with new glass plate leaving scratch
magnet has no reaction anywhere
after light clean 24 hours in clr did nothing to clean it no reaction
I hope the photos are ok I have trouble with them all the time Sorry.I look forward to any replies........Thanks,Steve

13th Oct 2019 00:52 UTCSteve Federico

the top I forgot to say rock is about 3x3 inches 1.5 thick and very heavy for its size

13th Oct 2019 00:53 UTCSteve Federico

the back of it

13th Oct 2019 00:54 UTCSteve Federico

a side view

13th Oct 2019 00:58 UTCSteve Federico

another side view.Gibsonburg Ohio is place found.Thank you again for any Help....Steve

13th Oct 2019 01:30 UTCBob Harman

Gibsonburg Ohio is in the Findlay Arch region of Northwest Ohio. It is a sedimentary environment so I think your example is an iron concretion or a very corroded pyrite nodule.

Parenthetically some fabulous iridescent fluorites came from the now extinct locality of the Gibsonburg Quarry.     CHEERS....BOB

13th Oct 2019 02:04 UTCPaul Brandes Manager

Appears like an odd iron concretion to me as well...

13th Oct 2019 03:46 UTCDean Allum Expert

Several aspects of it remind me of a pyrite/hematite concretion. With a microscope or magnifying glass, inspect the rough areas or vugs for tell-tale cubic habit pyrite crystals, now with a coating of hematite.

These are often associated with calcite.

If it is local, you may be able to find others which have weathered from the limestone matrix by looking for telltale rust staining.

13th Oct 2019 16:18 UTCSteve Federico

Thank You for the replies.Dean a 10x loupe shows tons of tiny cube shapes some bright gold and many have a dark grey metallic dull coating.I should say I have found many pyrite nodules etc. in my area and none compare in weight with how heavy this rock is.Thank You......Steve
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