I’m thinking concretion. @semmy-nou, if you scrub it with water will shell appear? If not it’s a concretion but if if you see shell underneath it’s probably some sort of snail. Right now there is too much limestone on it to tell.

I agree with at least a cephalopod ID. @Semmy-nou, would you like to update the taxonomy?

@semmy-nou Traditionally this has been classified as Orthoceras, however, a paper by Gnoli 2003 shows that there is high diversity in these sorts of straight cephalopods (squid-like creatures). I also read something that is restricting Orthoceras to the middle Ordovicean and cephalopods in other times have other names. This black limestone is…[Read more]

Hi @semmy-nou! Nice specimen. This is an ammonite, a relative of the modern day nautilus. Because of the minerals in this specimen, it’s likely from Madagascar. Do you have a picture of the other side? The cut pieces are hard to ID because they don’t contain many diagnostic features (although they are pretty). However, you can eliminate some…[Read more]

@semmy-nou At first glance this looks like a brachiopod. However, looking at the sides would help to see if there is a break in the rock (which might suggest it’s something else). Do you know where it was originally found?

@semmy-nou This is a trilobite. These are arthropods that can be identified by the three lines that run up and down the animal. Do you know where it was originally found and can you get a picture of the head (we call it a cephalon)? This will help further with identifying which trilobite it is. I’m going to tag @cameron-muskelly and @samantha-ocon…[Read more]