Fomes Fomentarius???

About a block from my apartment a neighbour has a big birch tree and all over it are these hoof shaped polypores. I had been eyeing them for months thinking they were a birch polypore, and finally the other day on my way home I asked if I could take one. They were growing on the central branches of the tree all over the place, so I picked one low enough to reach and just sort of pushed up on it until it came off. When I got it down it didn't look much like a birch polypore anymore, so I brought it home to inspect.

This is what it looked like:

It has a very hard top surface and the underside has very tiny light grey pores that bruise a darker grey/brown immediately when touched. The pore surface is so fine that the underside is velvety smooth. The pore surfaces bruises so fast that you can take the edge of something sharp and use it to write things on it! I had a lot of fun with that, by the end the underside of the mushroom looked like a page out of an old highschool notebook.

I tried to take a spore print of this mushroom, but it didn't seem to work. When I checked back the next day there was just a bunch of what looked like condensation in the glass, but not much else. I am a fairly inexperienced mushroom nerd, so I'm not entirely sure what that means.

Without a spore print or more experience I can't tell for certain what species this is but I am almost 100% sure it is in the Fomes species and if I had to make a guess I would say it is a Fomes Fomentarius.

If anyone has any questions, or has even come across this type of mushroom before, let me know!