Stegosaurus Tail Plate Armor - Real?

[Kribensis]

This is a much more recent acquisition that I picked up at an estate auction of a fossil collector that was identified as a Stegosaurus back plate. My own research has led me to conclude by the shape that if it is a Stegosaurus plate, it is back tail plate that would have been near the spikes. 
 

I have no concerns that the other fossils I picked up at the auction are genuine and were correctly identified. However given just the rarity of stegosaurus fossils, I think it’s probably not one and it was wishful thinking on the original collectors part. 
 

What do you think?  For all I know it’s just a flat rock. I don’t claim to have any real expertise. 

[Thomas.Dodson]

This looks like the metamorphic rock schist to me.

[Troodon]

Agree

[FB003]

I also concur.

[rocket]

yep, metamorphic, no fossil 

[Kribensis]

Thanks everyone.  Fortunately not a surprise.