Beach hunt and a fossil in my scoop

[treasurefiend]

I was waist deep water on a Chicago beach today and not finding anything but trash and got another bottle cap signal so when I brought the scoop up I found this fossil (oh and the beer cap too LOL) Any idea what its from or how old it might be. Is solid and like a black rock so its totally fossilized. I can't remember ever hearing of fossils being found on Chicago beaches but then fossils have to be everywhere right?
Thanks for looking and any info would be awesome, HH everybody.

 

[GatorBoy]

The first thing I should say is I really have zero experience in your area but when I look at that piece what it reminded me of was the pectoral fin of a fish.

 

[Harry Pristis]

I think it is a catfish pectoral spine. From a Chicago beach, it is not likely to be a fossil in the general sense of the term, but it is an interesting piece for your 'miscellaneous' collection.