I bought this bone about 5 years ago and at the time it was labelled 'ice age bone'. I thought it was pretty intriguing at the time but never found out what the bone had come from.
My best guess so far is that it's from a bison, or some cow thing (as you can tell I'm extremely scientific) but it's only just 30cm. Can anyone help me out? Would be great to finally find out what it is.