fossils or look alikes?

[Older The Better]

petrified wood or just layers and erosion?

looks like a vertebrae but could also be some mud petrified in the sand.
both came out of a gravel bar the surface rocks around here are Pennsylvanian

 

[Ninjafossils]

The first is probably not petrified wood. It more closely resembles weathered foliated rock, although I cannot be sure without examining the piece in person. The second looks like just a piece of sandstone with a weird inclusion. No fossil.

 

[usaranger]

could be a fossilized horse tooth, very similar to ones I have recovered in the past but also resembles bison...definitely a fossil tooth. No clue on the stone.