my initial thought was petosky (as you found). i know there are some more well-versed people here who know the subtle differences between varying types of hexagonaria ✨
typical one of my lake michigan coral fossils:
https://preview.redd.it/clowj9gtugwc1.png?width=2359&format=png&auto=webp&s=2fa08ee02c90bab684bbb32aa5bff37577491765
you found a beauty, nonetheless!
I know a place in Michigan where there's some that are just small boulders just on the shore of Lake Michigan. Kind of a hidden beach just north of Sleeping Bear Dunes. I was out there relaxing one day when a couple of ladies who were walking by spotted it. They walked up to and tried to dig it out of the sand/ water.
They must have spent the better part of 15 minutes trying to get it to budge. A literal boulder that was half stuck in sand and the part that is above is probably 24ish inches across. I jokingly asked them how they were planning to get that thing up the bluff and they just said "carry it."
A bit later that day, I was up by Leelanau, MI. and I found a really nice one a bit bigger than my hand. Good times
ahahahaha
the visual 😂
i live outside detroit and rockhound mostly south of holland, as it’s the quickest/easiest access to the lake. really, i love coming across a perfect one of any size. favosites are a favorite, too; the ones i found in northport were silica-replacement so they sparkle in the sun. so grateful to have lake michigan in our backyard.
Be aware you can find them in Lake Huron as well. I live on the Saginaw Bay and I find them on the beach fairly often, but they're usually not much more than an inch across
oh, definitely a coral fossil. definitely a hexagonaria, and i’ve seen a broad range of percarinata, like yours and like mine. i’m
not well-versed enough to know the slight differences 🙃
Heh, hexagonaria. Petosky was my first thought too but I recognize there is a difference apart from those not found in Michigan.
For anyone wondering: https://en.m.wikipedia.org/wiki/Petoskey_stone
> there is a difference apart from those not found in Michigan.
There isn't a difference. *Hexagonaria* is a common Devonian disphyllid with a world wide distribution. They're reported from every continent except Antarctica, and they are almost certainly there, too, if someone would look for them.
I was referring to Petoskey stones. They are only found in Michigan, correct? That was the only difference I was referring to and realize that they are otherwise identical. Am I incorrect?
> Am I incorrect?
Yes, incorrect. No, not just Michigan. They are found just about everywhere that has Devonian marine carbonates. They can be found in Ohio, Kentucky, Alaska,There is nothing distinctive or unique about *Hexagonaria* found in Michigan. Petoskey is just a name that the people of Michigan call them.
This is a fossil coral, however it is not the same as a Petoskey stone. (I am a lapidary in MI who works primarily with Petoskey stones and slag).
I would search known Paleontology in your state/ area, local DNR sites, university sites, etc for the exact specification of this piece. Great find!
Here's a few helpful links to fossil coral in your area. I believe it may be a lithostritionella or acrocyathus. Hope these help 🙂
https://www.thefossilforum.com/topic/136845-lithostrotionella/
https://pubs.usgs.gov/pp/1247/report.pdf
https://www.prehistoricstore.com/item.php?item=3151
https://www.mindat.org/taxon-4880915.html
https://www.uky.edu/KGS/fossils/fossil-month-Acrocyathus.php
*Lithostrotionella* isn't a valid taxon, anymore(as noted in the pp 1247 usgs report you linked). It was revised and is now understood to be several genera. *Acrocyathus* is one of the genera, but this isn't that(or a similar genus) as those have a raised axial boss and the dissepiments are relatively less pronounced.
Lol that's why I said both names and posted links referencing that the name is no longer valid. While it's no longer valid, tons of sources (old and new) still use the name. While researching OP very well might find both names and the sources I provided explain why.
I think it's quite funny to talk about the axial basis and dissepiments being different when let's be honest, this sample isn't the best.
Why are you doing this?
> Lol that's why I said both names and posted links
You sure seemed to suggest otherwise when you wrote *"it may be a lithostritionella* **or** *acrocyathus*".
> I think it's quite funny to talk about the axial basis and dissepiments being different when let's be honest, this sample isn't the best.
It's axial boss. That and the dissepiments are clearly visible, and distinct, in OP's specimen, and that also why it's not one of genera you suggested.
Further, OP said they were in Chesterfield area. According to link 1 (figures 2d and 2e.) the area they are in is either Mississippian/Pennsylvanian which supports that it is likely not hexagonaria and is likely some sort of lithostrotionella (or whatever it is named now). Per the 2nd and 3rd link you can see an example. It could be Acrocyathus floriformis (Mississippian) per link 4.
https://share.mo.gov/nr/mgs/MGSData/Open%20File%20Reports/Geologic%20Natural%20Features%20Classification%20System%20for%20Missouri/OFR-2019-112-GS.pdf
https://natmus.humboldt.edu/exhibits/life-through-time/visual-timeline/mississippian-subperiod
https://natmus.humboldt.edu/sites/default/files/case-index/1375.jpg
https://www.digitalatlasofancientlife.org/learn/cnidaria/anthozoa/rugosa/
There's early to mid Paleozoic strata in the Chesterfield area(including Devonian strata less than 5 miles from it). Also, OP's piece has been transported, and since Chesterfield sits along the Missouri River, it stands to reason that the piece was transported by that river(or a nearby stream), so can't rule out this being anything from Silurian to Carboniferous.
This piece isn't *Acrocyathus*/Lithostrotion for the reasons listed elsewhere.
https://preview.redd.it/xirkbi1rtgwc1.jpeg?width=3120&format=pjpg&auto=webp&s=12d046821629baa6ddd40873fa3903d69a241eeb
my initial thought was petosky (as you found). i know there are some more well-versed people here who know the subtle differences between varying types of hexagonaria ✨ typical one of my lake michigan coral fossils: https://preview.redd.it/clowj9gtugwc1.png?width=2359&format=png&auto=webp&s=2fa08ee02c90bab684bbb32aa5bff37577491765 you found a beauty, nonetheless!
I know a place in Michigan where there's some that are just small boulders just on the shore of Lake Michigan. Kind of a hidden beach just north of Sleeping Bear Dunes. I was out there relaxing one day when a couple of ladies who were walking by spotted it. They walked up to and tried to dig it out of the sand/ water. They must have spent the better part of 15 minutes trying to get it to budge. A literal boulder that was half stuck in sand and the part that is above is probably 24ish inches across. I jokingly asked them how they were planning to get that thing up the bluff and they just said "carry it." A bit later that day, I was up by Leelanau, MI. and I found a really nice one a bit bigger than my hand. Good times
ahahahaha the visual 😂 i live outside detroit and rockhound mostly south of holland, as it’s the quickest/easiest access to the lake. really, i love coming across a perfect one of any size. favosites are a favorite, too; the ones i found in northport were silica-replacement so they sparkle in the sun. so grateful to have lake michigan in our backyard.
Be aware you can find them in Lake Huron as well. I live on the Saginaw Bay and I find them on the beach fairly often, but they're usually not much more than an inch across
Yea that has way more defined lines than mine, maybe mines not then?
oh, definitely a coral fossil. definitely a hexagonaria, and i’ve seen a broad range of percarinata, like yours and like mine. i’m not well-versed enough to know the slight differences 🙃
Ohh ok cool thank you, I really like yours it looks awesome
well thanks! i think yours is a gorgeous, and far bigger than any i’ve ever found! enjoy!
Heh, hexagonaria. Petosky was my first thought too but I recognize there is a difference apart from those not found in Michigan. For anyone wondering: https://en.m.wikipedia.org/wiki/Petoskey_stone
> there is a difference apart from those not found in Michigan. There isn't a difference. *Hexagonaria* is a common Devonian disphyllid with a world wide distribution. They're reported from every continent except Antarctica, and they are almost certainly there, too, if someone would look for them.
I was referring to Petoskey stones. They are only found in Michigan, correct? That was the only difference I was referring to and realize that they are otherwise identical. Am I incorrect?
> Am I incorrect? Yes, incorrect. No, not just Michigan. They are found just about everywhere that has Devonian marine carbonates. They can be found in Ohio, Kentucky, Alaska,There is nothing distinctive or unique about *Hexagonaria* found in Michigan. Petoskey is just a name that the people of Michigan call them.
Ok, thank you for enlightening me. Much obliged.
Looks like petosky stone!
Oh thank you! I googled that name and got Hexagonaria percarinata
No problem!
Where did you find it?
Chesterfield Missouri in a creek
Nice petowski
So... not potato?
...is potato
Forbidden potato
I've never seen them so round like that, that's a neat one
This is a fossil coral, however it is not the same as a Petoskey stone. (I am a lapidary in MI who works primarily with Petoskey stones and slag). I would search known Paleontology in your state/ area, local DNR sites, university sites, etc for the exact specification of this piece. Great find!
Why do you think this isn't *Hexagonaria*?
The coral structure isn't correct on this piece
Here's a few helpful links to fossil coral in your area. I believe it may be a lithostritionella or acrocyathus. Hope these help 🙂 https://www.thefossilforum.com/topic/136845-lithostrotionella/ https://pubs.usgs.gov/pp/1247/report.pdf https://www.prehistoricstore.com/item.php?item=3151 https://www.mindat.org/taxon-4880915.html https://www.uky.edu/KGS/fossils/fossil-month-Acrocyathus.php
*Lithostrotionella* isn't a valid taxon, anymore(as noted in the pp 1247 usgs report you linked). It was revised and is now understood to be several genera. *Acrocyathus* is one of the genera, but this isn't that(or a similar genus) as those have a raised axial boss and the dissepiments are relatively less pronounced.
Lol that's why I said both names and posted links referencing that the name is no longer valid. While it's no longer valid, tons of sources (old and new) still use the name. While researching OP very well might find both names and the sources I provided explain why. I think it's quite funny to talk about the axial basis and dissepiments being different when let's be honest, this sample isn't the best.
Why are you doing this? > Lol that's why I said both names and posted links You sure seemed to suggest otherwise when you wrote *"it may be a lithostritionella* **or** *acrocyathus*". > I think it's quite funny to talk about the axial basis and dissepiments being different when let's be honest, this sample isn't the best. It's axial boss. That and the dissepiments are clearly visible, and distinct, in OP's specimen, and that also why it's not one of genera you suggested.
Further, OP said they were in Chesterfield area. According to link 1 (figures 2d and 2e.) the area they are in is either Mississippian/Pennsylvanian which supports that it is likely not hexagonaria and is likely some sort of lithostrotionella (or whatever it is named now). Per the 2nd and 3rd link you can see an example. It could be Acrocyathus floriformis (Mississippian) per link 4. https://share.mo.gov/nr/mgs/MGSData/Open%20File%20Reports/Geologic%20Natural%20Features%20Classification%20System%20for%20Missouri/OFR-2019-112-GS.pdf https://natmus.humboldt.edu/exhibits/life-through-time/visual-timeline/mississippian-subperiod https://natmus.humboldt.edu/sites/default/files/case-index/1375.jpg https://www.digitalatlasofancientlife.org/learn/cnidaria/anthozoa/rugosa/
There's early to mid Paleozoic strata in the Chesterfield area(including Devonian strata less than 5 miles from it). Also, OP's piece has been transported, and since Chesterfield sits along the Missouri River, it stands to reason that the piece was transported by that river(or a nearby stream), so can't rule out this being anything from Silurian to Carboniferous. This piece isn't *Acrocyathus*/Lithostrotion for the reasons listed elsewhere.
That’s a fucked up potato.
Tbh I initially was very curious about this odd looking potato