One of several stones...Game pieces or gastroliths?

[troy]

Hi all,

I'm a former member of this forum, I've never been to talkative but I've been lurking for years. I lost my user name & password after a computer crash. So here I am with a "first" post / question.

About 40 years ago my brother found several smooth white stones each about 1 inch in diameter. All of them had at least one concave depression in them that was very finely polished. One stone had 3 polished depressions in it and another polished surface. My brother gave me that one.
When I roll mine on a flat surface it acts like a really unbalanced toy ball & rolls in very unpredictable directions, it's very entertaining (at least to me). If it was worked by human hands, I wonder if that's intentional?

They were found in Southeastern Michigan, at the end of our street, on what was farmland. For all these years we thought that they were dinosaur gastroliths, because that's what my Dad guessed and he was really smart.

Last weekend my brother took his stones to a local rock & mineral show and asked a paleontologist about the stones. The paleontologist was sure they weren't gastroliths. He thought that they were Native American, possibly game stones and that they were very unusual & suggested we have a University look at them.

Here's a picture of mine. Oops I cant upload it. I get this error.
Unable to upload file DSCN0817.JPG. Error: This forum has exceeded its attachment space limit. Your file cannot be uploaded.

it's less that 1 mb. Any suggestions?

[Thunder69]

Hey Troy....welcome back...You have to use a photo hosting site like photobucket or similar ...And link it to here from there....John

[troy]

Thanks, I'll look into that. Meanwhile my avatar is a pic of the stone.

[snowmom]

how large? how dense? They remind me of the teeth that come from a pharangeal plate of a sheepshead drum fish... if it is not drum and is actual stone and not bone, think of looking into fossil remains of a similar sort?

[troy]

Definitely stone, possibly ceramic. I posted on a fossil forum, a few people think they're ceramic polishing media used on metal. I'm not sure but maybe...
We used to hunt Lucky stones on the beach in Ohio. They were bone plates from the head of fresh water Sheepshead.
Thanks.

[snowmom]

hope you figure it out. very curious!

[Fossilman]

Yes,any news yet? I have found gastroliths in Montana,while fossil hunting,they are interesting for sure(Most people walk right over them)...

[johnjsgems]

I'm no expert but collected what I'm pretty sure are gastroliths in UT. They look pretty much like river rounded pebbles but seem to have a slightly waxy feel. I was careful not to collect anywhere near any river course. I would find them scattered over about a 12' diameter with absolutely no other rounded rocks anywhere near. Convinced me anyway. Your picture doesn't look like gastrolith to me. It would be interesting to take it to a university or museum and have an expert look at it.

[troy]

This is a reply from a facebook page I joined. Pretty sure the person I'm quoting is a member here.
"I've got it! They are enteroliths. rocks made as secretions in the innards of horses around sand, a piece of hardware or some other thing, which can not be digested. I believe cows and maybe other animals get them too... google "enteroliths" to see similar images. It makes sense that you found them on farm land. Probably bones and other things near where you found them too? I knew those seemed familiar!"

[troy]

Hi,
I checked the stones hardness & a quartz crystal wouldn't scratch them, so they're above a 7 on mohs scale. According to google magnesium ammonium phosphate crystal (aka. Enteroliths) hardness is 1.5 to 2. Maybe I'm back to ceramic.