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Hello, Here are three fossils whose provenance is unknown...but likely somewhere in the US, and possibly Colorado. Does anyone have ideas for more specific IDs and possible provenances for them? Thanks. The first is what appears to be an echinoid, Eupatangus maybe? The second to me looks like a nautiloid steinkern/internal cast: Third is this plate of starfish:

Hello, I have another tricky ID request with no provenance, for this section of a heteromorphic ammonite. Technically I did get an ID and provenance from the seller as a Nostoceras malagasyense from Madagascar, but the preservation looks very different (more grey/white than brown). This was a chinese seller on that auction site who had that generic ID for a variety of pieces so I suspect it isn't accurate, and he couldn't provide more info when I asked. In the past I did ask about this specimen on this forum using seller-provided photos; I was told it looks instead like material from the Pierre Shale of USA, but was unable to further ID beyond "Nostoceratid ammonite". Now that I have the specimen in-hand and done some research I figured I'd ask again. Here are photos and some observations I've made: -Dimensions: the section is about 8 cm long; the chamber thickness is about 3 cm. -The preservation is of a chalky/pearly white+grey coloration, uncharacteristic of Madagascar specimens which appear sandy/grainy and brown. It has parts of white nacreous shell which are faintly iridescent in greenish-blue, though this is not as obvious in the static photos. Might indeed point to Pierre Shale, as I have seen Didymoceras specimens from there with a very similar look. -Based on shape of coiling, I suspect this heteromorphic section includes the last whorl of a helically-coiled turret/spire and the initial part of a U-shaped living chamber which coils "down" and away from the turret. I think this points to either Nostoceras or Didymoceras. You can see the direction of coiling changes sharply midway where the living chamber would've started. -The helical whorl section appears to have been in close contact with the whorl above it. There is a clear impression and maybe even part of the adjacent whorl's nacreous shell. I figure this is significant as it seems characteristic of the genus Nostoceras. Didymoceras stevensoni also has whorls touching each other, while D. nebrascense and D. cheyennense do not. -It seems to lack any tubercles/spines on the surface, which may rule out Didymoceras. -The oak leaf-like sutures are visible in parts, though I'm not sure how useful that is. So far, my best guess is that it's of the genus Nostoceras, and with the big assumption that it is from the Pierre Shale I've done some research into the heteromorphs that occur there: 1.https://digitallibrary.amnh.org/bitstream/handle/2246/1597//v2/dspace/ingest/pdfSource/bul/B251.pdf?sequence=1&isAllowed=y 2.Kennedy et al. 2000 9626-31949-1-PB.PDF 3.https://www.mindat.org/paleo_strat.php?id=13232 Kennedy et al. 2000 especially describes several heteromorphs from the Pierre Shale including a few species of Nostoceras. Nostoceras cf. N. approximans Nostoceras cf. N. obtusum Nostoceras larimerense Nostoceras cf. N. splendidum N. larimerense is the only one with a described body chamber that departs from the spire, but even then it is very slight and doesn't seem to point as sharply away as in my specimen. The holotype is shown below. Size is another inconsistency. The Nostoceras described here range from 2-4 cm height; the above N. larimerense holotype is ~4.3 cm tall. On the other hand, a single whorl in my specimen is about 3 cm thick, so it seems much larger than any of these described Nostoceras. Finally, all Nostoceras described here (as well as Didymoceras) have tubercles on the outer whorl faces, especially on either the last whorl or body chamber. But as mentioned, mine does not seem to have any discernable tubercles. That was a long post and I thank you if you've gone through it. I've tried my best to piece together what I could, and I'd appreciate anyone's thoughts. When it's all said and done I'm thinking it might just have to be Nostoceras sp., whether or not it's actually from the Pierre Shale.

Hey Gang, Need some help. I've got a couple trilobites and I realize I dont have confirmed ID/provenance. They were labeled as being from Morocco. 1)Maybe a Flexicalymene? 2) Not sure what this one might be and it looks like much different matrix and preservation than I've seen for Morocco? Maybe something like a Phacopsid? Thanks for the help in advance. Regards, Chris