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Identity HelpLightning Stone/MI Septarian question.

16th Nov 2014 19:02 UTCJim Meeker

I collect and polish a lot of Michigan Septarian/Lightning Stones. This one in the picture was somewhat different. I find many variations of the calcite color and opaqueness and sometimes find pyrite inside/outside. There is also another darker mineral I believe that I often see but do not know what it is. I'm including several pictures. You can especially see it in the white calcite to the left of the sphere in one of the pictures. Any ideas on what it may be? I find these stones in southwest Michigan. I am very much a novice in terms of identifying rocks/minerals. I would very much be interested in speaking to someone who knows more about these rocks, as they are the primary stone I work with. Thanks for looking.

https://scontent-b-lga.xx.fbcdn.net/hphotos-xpf1/t31.0-8/1941473_816226035079294_739428267782763845_o.jpg
https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-xfa1/t31.0-8/10619996_816225941745970_7400957554927677870_o.jpg
https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-xfp1/t31.0-8/10704207_816225948412636_8035727114428637600_o.jpg
https://fbcdn-sphotos-d-a.akamaihd.net/hphotos-ak-xpf1/t31.0-8/1398662_816226058412625_2643901907648054766_o.jpg
https://fbcdn-sphotos-h-a.akamaihd.net/hphotos-ak-xpf1/t31.0-8/10431422_816226011745963_1992930465413120688_o.jpg

16th Nov 2014 23:06 UTCPaul Brandes 🌟 Manager

Without actually seeing them in person, my first guess is that they appear to be hematite.

How many of these do you find, Jim? Enough to do some simple testing....

17th Nov 2014 01:11 UTCJim Meeker

I have quite a few. I'd have to find one with the dark spots but I'm sure I got more. I do find hematite in the same area, usually the kind mixed with jasper.

17th Nov 2014 04:05 UTCWayne Corwin

What color "mud" were you getting off that area while polishing?

Was it harder to cut thru?

17th Nov 2014 19:02 UTCJim Meeker

The mud was pretty much brown and not noticeably harder, but it's such a small area it's hard to say.
 
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