Unknown fossil with crinoids

[Icestar]

Time for the second batch of fossils that I've found out on the job. I have four to upload today and this is the first. I think I found this near the Michigan/Indiana border. There are two crinoid columnals in the rock next to the darker structure. Any help would be greatly appreciated, thanks!

[Icestar]

Other side. There is nothing on the bottom.

[Kane]

Judging by what appear to be septae in the darker, larger specimen, I would wager that this is a partially worn rugose coral.

[FossilDAWG]

I agree completely with Kane's rugose coral ID.

 

Don

[ynot]

I agree with Kane, horn coral.

 

 

[Icestar]

Thanks for the replies!