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Was wondering if this spine is from a plesiosaur or mosasaur. and is it a neck, tail or trunk spine? Found poorly preserved in Pierre shale sd. There are a few ribs there too. The reddish end pic is where I did a clean break form some more of the fossil which is in different jacket. I roughly cleaned this spine but don't think it's worth putting more time into with all the gypsum.

Pierre shale, Millwood. Western Interior Seaway, Campanian.

One week fossil collecting trip out west, my sixth time in the past six years. Flew into Denver. Rented a car and headed down to Castle Rock where I spent the night at a motel. Next day drove up to Florissant Fossil Quarry. It was Wednesday and they're normally closed during the week in September, but I made special arrangements for a few hours visit. Compared to my two previous visits there, didn't do as well. The other times, I was there for the whole day, this time was just for three hours, and they had had a considerable amount of rain recently and so the shale was more crumbly and more difficult to split. Here are some of my finds. Plants:

A new mosasaur, related to the genus Clidastes, has been described from the Middle Campanian Pembina Member of the Pierre Shale Formation of North Dakota near the town of Walhalla and has been given the undeniably cool name of Jormungandr walhallaensis, after the world serpent of Norse mythology! Zietlow, Boyd and Van Vranken, 2023. Jormungandr walhallaensis: a new mosasaurine (Squamata: Mosasauroidae) from the Pierre Shale Formation (Pembina Member: Middle Campanian) of North Dakota.

Linked is a 3D model of a nearly perfect Hoploscaphites nodosus ammonite. Models can be viewed using this website: Online 3D Viewer or through other software. This is a 3D model of an actual fossil and is not a "recreation", but since my last upload was moved here this is where I will upload the rest of my 3D scans. If anyone else has any good ammonite or inoceramus finds from Colorado please share them with me and tell me a little about them. I've been reading some of Bill Cobban's papers about the invertebrate paleontology of Colorado and I've gotten really interested in what can be found around here. Thanks! -Sam 1195980117_Hoploscaphitesnodosus-Kprl(1)-1.glb

Hello! I am trying to clean this beautiful mosasaur pictured below, but I am really struggling with some old paleobond thats already been used on it. I have been somewhat successful with using a liberal amount of acetone on the bone, which I scrub in with a toothbrush. This has worked, but there are certain regions where the the glue was used on gypsum crystals and model clay, which has effectively cemented the bones of the lower jaw together. I've also been using a regular paleoarrow. My goal here is to get it as clean as possible, NOT to specifically separate the natural occlusion of the teeth. The plan is to display it at a museum (Also, any wild guesses as to the genus of this pretty lady? I was thinking latoplatecarpus)

Was wondering which plesiosaur species it might come from. Pierre shale sd 2ft by 2ft. It was broken before fossilizing also encrusted in crystals. Some parts are only .5in thin. Wasn't sure if it was worth picking up. It's a complete rear pelvis. Found verts and other leg bones by it. It was facing up like in photo. But not sure which side is which when it was alive. Bottom point is where it attaches to leg. The bottom of the nob on the left also looks like it was attached to something. As it shows cartilage remains. Maybe it attached to other side pelvis? I tried using this page to id it.

Wondering if the species can be ID. Found in Pierre shale SD. Both teeth were touching the pointy bone. Is that a jaw? Also I put a b72 alternative on them but it sometimes leaves a white film on it which you can see in the photos. Is there a way to avoid this? Thanks!

The first mosasaur tooth I found in Pierre shale sd. 2in long poorly preserved. Was wondering if it was a shedded tooth or part of jaw? Also what species might it be? thanks!

What could of made this? Thanks! I mostly find mosasaur pieces but never found anything this cool before. Was in a creek so not sure where it came from. But SD Pierre shale formation is around the area. 2in long. I haven't cleaned it yet.

Found these 3 fossils 1ft apart from each other at bottom of a hill. Are the 2 vertebrae from the same area of the body as the mosasaur paddle arm bone? What's the chance this is all from same 1 animal? If so I might try looking for where they came from. Is there a technique to removing a side of a hill to find the source? Thanks

Found this unusual broken bone in Pierre shale with a vert right by it. Where on the mosasaur body might it have come from? Thanks!

Found this big bone with a mosasaur vertebrae near by in Pierre shale. This is the biggest mosasaur single bone I've found. Is poorly preserved and started to weather. Is there enough to tell if it's femur or humerus? I compared it with other mosasaur but couldn't find any that were this round. What species might it be? Thanks

Found what looks like fish jaw with tooth and skeleton. There are many pieces of this fossil but only showing part with jaw. Was found poorly preserved in Pierre shale SD. Wondering which fish species it might be? Thanks!

Found in Pierre shale in Sd. Might be from a concretion. the 2 parts are not from same creature it seems. Was also wondering what species it could be? Thanks

A cool piece frozen in time from the day they were buried together. Also a decent size Inoceramus shell for the area and always fun to find an ammonite. This piece is from Boulder, Colorado.

From the Pierre Shale of Fort Collins. Found next to a lot of Inoceramus bivalves not too often you see something like this. I initially believed it was a branch of wood that was buried but I'm thinking it could be a rib bone most likely from a mosasaurus. Any feedback is appreciated just thought someone should look at it.

A little slow in getting around to posting. 2 weeks ago my son and I got back from our yearly trip up north for fossil hunting. Like most years, we haul the tenement on wheels with us to save the crazy costs of hotel stays. We started out for the first 4 days in the Hell creek, digging with Walter Stein of PaleoAdventures. The first day was a little slow with lots of small tumbled bone bits and spitter teeth. Only bigger find was an unknown that I began to uncover, but didnt complete that day. The second day we changed where we were excavating and I found the first tooth of the trip. I found a great pinecone, the second ever, and 13 years since our last. A beautiful Nanotyrannus (our biggest ever by a hair). It had some acid etching and gypsum fouling, but would prep out well. 3rd day we went back to the first spot where I finished uncovered my unknown which turned into an unknown long bone next to a Thescelosaurus left ilium. The ironstone rocks it was bound in were crazy so it took me all day to finish exposing the surface. Day 4 was back at the ilium and clearing above it so I could pedestal and put on a plaster jacket. In the process of clearing, I uncovered an croc lower left jaw with a single tooth still in place. So then day 4 was spent finishing the ilium pedestal and pedestaling the jaw. The ironstone made the work slow, but I did pop out a beautiful (and huge) mammal tooth in the process! Walter said it may be the largest mammal tooth from the HC thats he's seen. We had originally planned to head over the fish quarries of Kemmerer WY, but we decided to stay and explore the Pierre shale and museums for a few days and then dig with Walter a couple more days. We went to the Belle Fourche reservoir (actually the Carlisle shale, not the Pierre) to look for ammonites and shark teeth. We did manage to find a few partials and one possibly complete ammonite, but we struck out in the search for teeth. After that we started to do some map recon of govt lands in the Pierre formation and driving back roads to find an area we wanted to try. I had little hope of being success in such a blind hunt, but we hit a motherload site I named "baculites heaven". They were everywhere. it was difficult not to walk on them in some spots. We filled 2 cardboard boxes with what we could carry and left super happy! Also found a set of deer antler sheds as a bonus. Now, last year we hunted a site on the invitation of Neil Larson. It a fairly well known site among many, and universities make trips to collect baculites there. The spot we found was every bit as good as Neils site, except we couldnt drive directly to it, and it required a bit of steep terrain hiking. The next 2 days were spent museum hopping. We visited the Mammoth dig site museum, the "world fossil find finder" museum (both in Hot Springs) and then the Black Hills Institute in Hill City. Day five in the Hell creek was back to the ilium and jaw. We started the day by jacketing and flipping the fossils, which was still a task with all the ironstone, but we finally got them out. Right after that, my son began excavating below where everyone else had worked. Basically below where all previous diggers had been sitting. Within minutes he popped out (literally it popped up!) was the best T.rex tooth (and only 3rd) we've ever recovered. A gorgeous 1.5 inch pre-max. Amazing that among all that ironstone, where people had been walking and sitting, and coming free with an ironstone rock removed, it was in perfect shape and not broken or even cracked. Our last day was lots of BOBs, chunks of turtle shell and more spitter teeth. Although not our find, I had to share this wonderful, complete Trike rib recovered. over the last couple years, more and more elements of a very large triceratops have been recovered, which is looking to be parts of a disarticulated animal. I don't have pics, but it also seems as if a disarticulated T.rex is also present. about 8 years the first femur of a rex was found while exploring, and now in the same location, more rex elements have been becoming uncovered, the last being a second femur. So, another trip is in our history book, with lots of great new fossils found. As a side note, a few years ago my son found a mammal jaw which was later sent to the Burke museum for study. This new mammal tooth uncovered is hopefully going to be part of the same collection, although Denver would probably like to have it too. A Pachy skull hornlet my son found last year, has a new home in the Melbourne museum. When I find out where any other element find a home, I'll update.