Banquet Left-over?

KeithKnight's Challenge Day 18 - Left-overs

I found this object on the Thames foreshore back in the early summer during a day trip to London. I believe it is the remains of an animal bone, though i have been unable to identify it from any anatomy pictures found online. From its colour it has been in the water for some time, and I thought the shape and feel made for an interesting object.

Looking for inspiration for todays challenge, it bought to mind an event in the spring when I attended a medieval banquet in celebration of a successful project delivery. History tells us that earlier periods had a somewhat hands on approach when eating meals, and gnawing at big bones was common. Once the meal was over, the Thames was handy for disposing of the remains.

Would it be too fanciful to imagine that this object was the left-over from one such meal - maybe even one held in the nearby Tower of London?