Possible Mazon Creek Jellyfish and other invertebrates

[AstroRaptor56]

I headed out to Mazon Creek IL a few days ago and came back with some fair nodules. I found a big nodule(6) and used the freeze thaw method to open it, I think it might be a jellyfish but I’m unsure, as I guess it could be nothing. 1 and 2 just have irregular shapes and I believe are made of pyrite. 3,4 and 5 are nodules that did not open from freeze thaw so I broke them with a hammer, and they have some white marks but I’m not sure if they are anything at all. Help with any of these finds would be awesome, and I had quite the adventure at Mazon as it rained and was quite filled with ticks!

[Rob Russell]

Your big one is indeed a essexella jellyfish. The two on the left look like pyrite, or ironstone, nodules, IMO. It’s all a bit blurry. 

[connorp]

6 is a nice Essexella. 3, 4, and 5 are nodules with pyrite inside. They are fairly common but sometimes you can find cool shapes. 2 looks like a pyrite "ball". I have found some in a quarry that exposes the Francis Creek Shale (where the Mazon Creek fossils come from) and both overlying and underlying strata. I'm not positive what layer they come from. I don't know about 1.

[GeschWhat]

I can't tell for sure from the photo, but #1 looks like it could be a spiral coprolite. Could I see a closeup at different angles (on a plain surface)?

[AstroRaptor56]

9 hours ago, GeschWhat said:

I can't tell for sure from the photo, but #1 looks like it could be a spiral coprolite. Could I see a closeup at different angles (on a plain surface)?

Hello! Here are some more angles, I looked at it closer and it definitely does spiral up, I’m quite sure that it’s made of pyrite, but I don’t know if coprolite is ever in a pyrite form