Strange fossil from Mazon creek area today

[Jcwitte]

First fossil? ever found from hitting rocks with hammer... I’m afraid to try to expose any more of it. Any ideas as to what it could be. 
 

First pics with ruler for scale and then without for better detail. I found it along Monster lake in an area where the sides had very recently eroded to expose lots of coal.

[GeschWhat]

It looks like a trilobite cephalon, but wait for the experts.

[Tidgy's Dad]

It's a calymenid trilobite cephalon. 

Nice find. 

[Jcwitte]

Well that was a fast ID. Thanks much! Obviously I am new at this. I’ll have to research how to expose the rest of it.

[Tidgy's Dad]

28 minutes ago, Jcwitte said:

Well that was a fast ID. Thanks much! Obviously I am new at this. I’ll have to research how to expose the rest of it.

I would very carefully poke it gently with board pins.

Others may have different suggestions. 

[Thomas.Dodson]

11 minutes ago, Tidgy's Dad said:

I would very carefully poke it gently with board pins.

Others may have different suggestions. 

I'd start with this at the very least. Do you have an air scribe?

 

It's certainly a neat find. I found a couple non Francis Creek Shale fossils around Monster Lake as well and since then I've wondered how much remnant material is around the pits (like the rest of Illinois). This just makes me more curious.

[connorp]

There's a lot of glacial erratics scattered across Pit 11. But I would think this is from local Silurian dolomite instead.

[Jcwitte]

I do not have an air scribe. I am a complete novice... I actually cracked my finds open today with an old wrench. I considered the freeze thaw method but unfortunately I am not patient enough. Hopefully I can dig deep and find patience enough for my next haul. 

[Thomas.Dodson]

3 minutes ago, Jcwitte said:

I do not have an air scribe. I am a complete novice...

Not a problem. It could probably done mostly with the pins if patient. Either way I'd start with the pins.

 

4 minutes ago, Jcwitte said:

Hopefully I can dig deep and find patience enough for my next haul. 

I'm 99% sure you mean figuratively digging for your patience but just to be clear there is no digging allowed in the Fish and Wildlife Area.

 

8 minutes ago, Jcwitte said:

I actually cracked my finds open today with an old wrench. I considered the freeze thaw method but unfortunately I am not patient enough.

Connorp and I alluded to this but this is NOT a Francis Creek Shale concretion so I probably would have hit it with a hammer too. The actual concretions should be done by freeze-thaw. People disagree over when to give up on freeze thaw cycles and finally hit it with a hammer but basically everyone agrees to start with the freeze-thaw. You are of course free to things your own way but I (and many others) feel freeze thaw is the only way for the concretions. You'll regret it forever if you break a significant find by skipping freeze-thaw and using a hammer. Then you'll wish you just used freeze-thaw from the beginning.

[FossilNerd]

You could check out our fossil prep section for suggestions regarding exposing the fossil a bit more. 

 

There is a lot of great information in the prep section, but here are some of the pinned topics that you may find most helpful.