Fossil id help

[DJE]

Hello i found this rock and to me it looked like it has a fossil embedded in it and was wondering if there is, and if so can anyone identify it please. Thanks Darren

[DJE]

more pictures

[Ludwigia]

Exactly where did you find it? How big is it? Can you say anything to the stratigraphy?

[DJE]

I found it on the floor in neath south wales in a small woods whilst walking

[Darbi]

It appears to me as a concretion.

[Ludwigia]

Your stone must be carboniferous then if it's from Neath. I don't think it's a fossil although it does slightly resemble the form of a bivalve shell.