Need help with small fossil id

[Billymac]

My sons just came back from Big Brook New Jersey with some nice finds.  I found this tiny little specimen to be interesting.  It is about 1 cm long and looks like a thorn, but I am not sure what it is.  I’ve enclosed three pics, top view, side view, and bottom.  The pics are under an 8x magnifying glass.  I hope the pics are clear enough.  Thanks for any help with id.

[Rockwood]

Dermal denticle from a ray. 

[Billymac]

Thank you so much.  We were thinking along those lines.  I appreciate your help.