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Hey everyone. I’m looking for more information on Goniatites found in the Mississippian Coldwater Shale. I found this little guy today after cracking open another packstone (second to last photo shows the host stone) I picked up in South Haven, Michigan, along the shores of Lake Michigan. Any insights you could toss my way would be greatly appreciated. Thanks so much for your time!

More Lake Michigan - Long Beach, IN finds. #1 - just a rock? #3,5 - horn corals? #4 - favosite? #8,9 - more coral? Sorry about the photo quality/quarter as a size reference. It was the best I could do for now. Thanks for your input

I found this on the shore of Lake Michigan in Long Beach, Indiana– just south of the Michigan border. I have no clue what I am looking at. Any ideas? Thanks for your help!

Hello From Door County Wisconsin. I have been here about 12 years now and collecting fossils from here for almost all of it. My interests are in all fossils but my range is mostly sularian right now. I am currently wondering if someone can explain what a silicified stromatoporiod is. I understand it has silica but the process I don't fully understand. Also is it considered a type of agate? I see this subject gets to be a muddy topic. I just want some clarification on how silicified works. I included a pic of one from my collection. Thank you for any input.

Greetings all! Recently pulled this from south shore Lake Michigan near the Mack Straights. Curious as to what the fossilized material is inside the upper shell half which is approximately 2.5cm across. Any ideas? Bonus points if you can identify the shell too Thank you!

Hi everyone, I just got to spend a couple days looking for fossils at Lake Michigan and came across a few that I couldn't identify. In addition to loads of Petroskey stones and Charlevoix stones, I came across the attached rock. Any thoughts on what may have been captured here? The stone is about 4 inches across at the longest (top to bottom in the figure). Location: Charlevoix, Michigan.

Relevant info first: This was found in Petoskey Michigan while looking for Petoskey stones. It was found in partially buried in sand. It is quite large and rather heavy. As pictured in picture 5, there is some sort of opening at the end? I can't get a very good picture of the inside, it's hard to get light where i need it and take a picture. the hole looks to maybe be about a 1/2 mm deep, and less than that wide. I took to reddit, albeit with less detailed photos and was told it was a straight shelled nautiloid cephalopod from the paleozoic, and that it was a brevicone, which I'm hoping someone can confirm or deny, or point me towards relevant info. I was trying to find more and found this on your forum, which is the first thing I've found online that actually looks something close to what I have: Anyways, Thanks for looking, and any help you can offer.

Hello again! I received another trade today and was told this was a fossil found at Lake Michigan. I'm not entirely sure it's actually a fossil and I definitely don't know what it is if it does happen to be a fossil. I couldn't capture it with the camera but when I rotate it there are tiny glittery areas on some of the surface.

Last week we took a ride to Lake Michigan to do a short search before the weather turned bad. The previous day had strong winds with large waves and I thought we might find some interesting things. We found plenty of Favosites, Halysites, and Rugose corrals as well as some of the other usual finds. The one unusual find was what I believe to be an internal mold of a Pentamerus oblongus brachiopod. I don't find many brachiopods and as such I'm not 100% sure on my ID. Please confirm or correct. Thanks in advance. Jim

We are interested in what the long skinny fossil with the flanges or fiber things are that look like a swimming thing. This fossil was found on the beach in Milwaukee Wisconsin United States on the shores of Lake Michigan. It was found on October 27, 2020.This fossil was found on the beach in Milwaukee Wisconsin United States on the shores of Lake Michigan. It was found on October 27, 2020.

Found on lake michigan. Im not sure how to tell the difference between fossil and a piece of pottery. Any advice?

My new find of the week was located on the shore of Lake Michigan in Glenn Michigan after some rain and high storms. I am needing help in correctly identifying this, i have some ideas but yall know more than i. And really wanting to clean this up. Was going to soak in vinegar but thought id ask before i touched it with anything other than dish water. Thank u

We found the following in Harbor Springs, MI in July. Initially thought it might be petosky, but it’s a lot lighter in color and smaller markings. Thanks in advance!

Found on the beach of Lake Michigan in Sturgeon Bay, WI this past week. Approx 1" w x 3/4" h x 1/4" deep. Thank you!

Hello everyone, I hope I find you well in these trying times. I live near Lake Michigan and sometimes I find fossils with my family in the lake. I used to have a fossil kit as a kid and am a life-long lover of all things science. I tried to change my profile picture but an error just kept popping up saying I needed to be signed in (which I already was). Maybe I'll try it in Chrome but for now I'll look like a newb who just doesn't know how. Feel free to introduce yourself and to talk to me on the threads, I'd love to meet you guys. Anyway, Thanks for reading. -MP

Hi all, Is this a trace fossil, worm holes? If yes, that would be the first I've found. The holes measure about 1mm to 2mm in diameter. I think it's odd that all of the larger diameter holes are perfectly parallel to each other, while the smaller diameter holes seem to run perpendicular to the larger ones. Also, what are the dark thread-like shapes all over this rock. I've never seen those on my finds either. Rock measures 2cm tall, 1.5cm wide. Lake Michigan beach find, WI, this could be either ordovician, silurian or devonian. TIA! front: back bottom

Found this rock on the shore of Lake Michigan near the beach canal entry to Lake Macatawa. Looks like the inside of a walnut. Thanks

This rock has me puzzled. The sides look like they might be the laminae of a stromatoporoid. The top of the rock though, lacks any trace of mamelons and the wavy lines between them that I typically see on stromatoporoids. Instead the rock is full of Cheerios ;-). So I'm wondering if this is something totally different. Maybe geological? Oddly preserved oolites? But then, what are the layers visible on all the rock's sides? Dimension: 1.5" long. TIA to all! Detail of top: Side:

I found all the crinoids below at Lake Michigan beaches in Illinois. (Silurian, Racine formation) I have to admit, I used to not pay too much attention to the ubiquitous crinoids on my hash rocks. That is, until I started to look at them with a clip-onto-the-phone microscope. I quickly found that crinoid disks aren't all the same and are actually quite beautiful and intriguing. Also, finding a pretty little crinoid calyx at the beach got me to look for more like it and low and behold, a short time later, I did find another one. I do believe they are very rarely found at Lake Michigan beaches, unlike the ubiquitous petoskey stones or honeycomb corals. So I've been trying to research Silurian crinoids from this formation, alas with very little success. Oh, for the lucky people who find Devonian crinoids, bibles have been written about those, I'm so jealous! So I'm turning to TFF once more to hopefully find additional information. Is anyone here familiar with Silurian crinoids from the Wenlock epoch? Is it possible to narrow down ID of at least some of these even though I don't have a single stalk or stem segment with the calyx and vice versa. # 1: Maybe a Crotalocrinites or similar? I'd love to know what its calyx looks like. Love the flower shaped lumen, it's so pretty! For comparison, this is a pic of Silurian Crotalocrinites from the British Geological Survey: I'm not 100% sure that they occur in the Racine formation though. Also, the lumen takes up more space within the disk than the lumen on my specimen above. Otherwise the flower shape seems a perfect fit, but hard to tell if the crenolae under the dolomite glaze on my piece are as fine and tightly spaced. Maybe a it's a close relative? #2: I haven't found a single image or description of a crinoid stem that looks like a perfect medieval tower. Anyone here that's familiar with such patterned crinoid stems? (Love the Danish pastry look on its top and bottom too) #3: I assume this poor crinoid was parasitized by some other live form? I know that brachiopods have been found attached to crinoid stems, as illustrated on Chicago's Field Museum work-in-progress website. But I don't think that's what happened to this one. What could have caused such extensive damage? #4: I think this one does have a cirri scar on its left side below. Detail of what I think is the scar in the 2nd pic. The following stem disks are all microscopic in size, less than 5mm: #5: I hope the lovely star-shaped lumen might make it identifiable. #6: Same as for the above, the ship's wheel lumen surely should help with ID? #7: Another Crotalocrinites or similar? Flower shape seems a bit different though, assymetrical. #8: I've found quite a bit of literature about star shaped jurassic crinoid columnals/ossicles, but nothing about Silurian ones. This one, sitting in limestone actually has the widest diameter of all columnals in my collection. Ø = 1.5cm. #9: First calyx. I think this one is very nicely preserved. Ø1cm and height: 1cm. Is it possible to narrow down its ID, despite missing the stem and arms? Also, in most images of crinoid calyces, the brachials visibly grow out of the side of the calyx. Not so with this one. Would they have grown out of the top side by side with its mouth and anus? #10: Second calyx. It's a bit larger, about 2cm wide and 1.5cm tall. Not sure what its original shape used to be, as it's been tumbled and worn and seems to be missing parts on its side. The top is hidden in matrix.

I found this stone along the shore of Lake Michigan. I would appreciate any feedback as to what it might be? Thank you!

Hi all,I'd appreciate your help with this Silurian Lake Michigan fossil from the Racine formation. I've done some research and found a family of Silurian colonial horn corals that have members which do look very much like my find. It's the Arachnophyllidae family. I'm not sure if they occur in the Racine formation though. Are these badly preserved stromatoporoid mamelons next to the horn coral? The rugose coral is growing on a stromatoporoid reef? Calyce detail: Here is a North American Silurian colonial coral that looks similar. It's Arachnophyllum kayi. Found it in a USGS report about silurian horn corals. So now, to the "bumps". Mamelons of stromatoporoids? Thanks so much to everyone for your thoughts and input.

Picked up this stone a few years back while visiting the area north of Traverse City on Lake Michigan. Lots of Petosky stones on this beach, but this really looked unusual. I’ve had some time to look at it while at home lately and wondered if anyone had any ideas? So curious because of the triangular shapes and line patterns.

Hello everyone. As usual, I need your help with one of my finds. It seems this small rugose coral has a buddy. At first I thought the the tiny "bump" was just a bit of debris sitting on top of the coral. But now that it's enlarged, it looks to me somewhat similar to a crinoid. I'm not really sure though, I've never seen a crinoid preserved anything like this. Surely it's not part of the horn coral itself, or is it? Thanks to all for your input. Detail:

Please help me to identify these two fossils. When I picked up these rocks, I thought I had found corals, but now, looking at them from all sides, I'm stumped. What throws me, is that the pattern on each of the two fossils looks the same all around the rock. No vertical structure or growth pattern, anywhere. So even if these are just broken off pieces of a much larger fossil, corals still would show vertical structures on the sides, right? But no "sides" are visible here. Confusing. Thanks so much in advance for taking the time to share your knowledge. #1: Dimensions: width is 2.2cm; height is 3cm, the individual circles vary quite a bit from <0.5mm to >1mm. Detail: #2: I wouldn't mind if this one is geological, as I collect more purely geological rocks than I do fossils, but I don't think this one is just geological. Dimensions: width: 3.5cm; height: 2cm; individual "dots": max 1mm

I picked up this jasper for its banding. Only later, when checking the rock through my hand lense did I discover what I think are a bunch of little rugose colonial corallites at the top and bottom of this rock. If these are indeed corals, all but one lack most detail in the center. If septa are faintly visible, they look differently preserved than on any of my other coral specimens. Mostly it's just circle after circle here, and areas full of "pores". Now that I'm looking at them on my larger screen, the "pores" themselves seem to be corallites - microscopic ones. The black dots are in the center of honeycomb like shapes. I'm confused now, are these the fossilized remains of one or two type of corals, or maybe a colonial coral and a bryozoan? Sorry about the bad quality and distortion of the pictures taken through a microscope lens on my phone. Please help me ID these tiny hurricane look-alikes. As always, thanks in advance. Here a couple of them in various states of preservation. Lots of them have a vug where the center of the corallite would be. Here the circles look like growth rings and in some areas the "pores" are clearly visible. #1: This one is the only one with detail in the center. Septa? #2: a vug at the center seems all that's left here. #3: Just pores in the center, and in between the circles, maybe the faintest lines that could have been septa? #4: Area in between corals, with faintly visible honeycomb shapes: Detail of the above: Another area in between, looking somewhat different again: