Not sure if its a fossil

[Daisyjpoe]

This rock/fossil looks like it has a skin on it. The outer layer of it is a deep maroon/purplish color. The shapes on the outer layer are all similar but no 2 seem to be identical. It was found about half way down the side of a mountain in Monroe County WV. The side that the outer layer/skin is chipped off there is visible evidence of the pattern in the underlying material. Its about 9 inches long on one side an 6 1/2 on the other. The underside has several rectangular shapes that look like something. I've tried to look it up but can't find anything similar other than the dried and cracked mud pics. I'm pretty sure this isn't a layer of mud on the outside. The last 4 pictures are the top( 4th from last with measuring tape) and the bottom(last 3 pictures)

[Sagebrush Steve]

Not sure of the geology in WV but the surface reminds me of slickensides, which occur when two rock surfaces slide past one another under great pressure, typically with metamorphic rock.

[Fossildude19]

I'm seeing the beginnings of counter septarian structures in the first photo.

Geologic in origin, rather than biologic.

[Daisyjpoe]

Thank you!