Great Lakes fossil (Lake Huron)

[sunshinegirlie]

Hoping to find someone who knows what this is. Obviously, it's some sort of seashell but I was hoping for more specific information and opinion. I found it while snorkeling last week in Lake Huron (Straits of Mackinaw region). Thanks! 

[Fossildude19]

Welcome to the Forum.  

This looks like a worn cross section through a gastropod. 

Not sure of the geology of the area, though. 

Regards,

 

EDIT: It appears that the Bois Blanc Formation is in that area - Early Devonian in age.

398-415 million years ago. 

[sunshinegirlie]

12 minutes ago, Fossildude19 said:

Welcome to the Forum.  

This looks like a worn cross section through a gastropod. 

Not sure of the geology of the area, though. 

Regards,

 

EDIT: It appears that the Bois Blanc Formation is in that area - Early Devonian in age.

398-415 million years ago. 

Very cool! Thanks!! 

[Ludwigia]

I agree with Tim. Gastropod.

[Max-fossils]

Awesome find!

I love seeing cross sections like this, because you then get to clearly see the inside of the shell, and the chambers. 

 

Congrats on the find,

 

Max

[sunshinegirlie]

Thanks!! I was in the area where Lake Michigan meets Lake Huron. Fun place to snorkel! I was looking for puddingstones but came across this, instead! 

Edited August 21, 2017 by sunshinegirlie

[Kane]

Any chance for a more detailed close-up of the specimen at higher resolution? It very well might be gastropod, but there is something about the cherty texture on this one that resembles some of the corals I've found in that formation. Although the shape may tend toward gastropod, some rugose corals have taken on suggestive appearances, such as tight coiling.

[ynot]

@Ludwigia, @Fossildude19

This shell looks like it has septa, would that mean it is a gonite and not a snail?

[Fossildude19]

16 minutes ago, ynot said:

@Ludwigia, @Fossildude19

This shell looks like it has septa, would that mean it is a gonite and not a snail?

I don't think there are septa.  I see mineral veins.

They aren't evenly spaced, as one would expect with septa.  

[Ludwigia]

6 hours ago, ynot said:

@Ludwigia, @Fossildude19

This shell looks like it has septa, would that mean it is a gonite and not a snail?

Sorry ony. I don't see any either. Like Tim said.

[sunshinegirlie]

10 hours ago, Kane said:

Any chance for a more detailed close-up of the specimen at higher resolution? It very well might be gastropod, but there is something about the cherty texture on this one that resembles some of the corals I've found in that formation. Although the shape may tend toward gastropod, some rugose corals have taken on suggestive appearances, such as tight coiling.

I only have my phone to take pictures with, but here are a few more. 

Edited August 21, 2017 by sunshinegirlie
Image quality

[ynot]

8 hours ago, Fossildude19 said:

I don't think there are septa.  I see mineral veins.

They aren't evenly spaced, as one would expect with septa.  

 

2 hours ago, Ludwigia said:

Sorry ony. I don't see any either. Like Tim said.

Oh well, not the first time I was seeing things that were not there.

[sunshinegirlie]

This is as close as I could get to preserve image quality. It was found snorkeling in Michigan. Straits of Mackinaw area where Lake Huron meets Lake Michigan. Found near Mackinac Island. 

[Kane]

I am leaning more towards coral impression. Despite the very suggestive coiling, note that the ribbing is not continuous. Also, looking over Bois Blanc Fm gastropod specimens, I haven't encountered any that have ribbing. 

[sunshinegirlie]

I also found this one. Is this a fossil? 

[ynot]

That one is a horn coral.

[Kane]

That certainly is: a rugose coral.   EDIT: Tony beat me to it - fastest keystroke in the west!  

[sunshinegirlie]

5 minutes ago, ynot said:

That one is a horn coral.

Thanks!