Not found every day: Petrified bone

Today's find: Fossil bone? The thing certainly doesn't look like a broken-off piece of a plaster figure. At least I couldn't find any fractures on it.

I also doubt the theory of a "recent bone", which would basically suggest that it is still a flawless bone.

The piece is only 8 cm wide and weighs just under 150 g after all. Completely solid, apparently not hollow either. But otherwise it has all the characteristics of a vertebra or similar bone. Very fine-pored in some places and the finest fissures are visible. 

But the thing is not porous at all. The mineral freaks in the forums tend to reject such sightings and finds, as it seems there. With similar finds they claim: "Whether it is fossilised - which I don't believe - you can easily try it out. If you have a small fretsaw or a file (a nail file will do) at home, try sawing or filing the bone. If you can see a removal of material, it is a recent bone and not a fossilisation."
Well, I used a nail file and nothing came off. OK, maybe I'll try a harder file. But I'm sticking to my guns: the thing is hard as a rock (and therefore a stone).

Interesting find, excavated from the edge of a forest near Myhl.