Ozmeath

I'm not much of a handy man, but being a biologist I would guess that you could 'burn' into the horn seeing that it is mainly just hardened collagen. However, I can only imagine the stench of the burning horn.

I also don't know about boiling the horn. I'm sure someone has expertise, but it seems like that could leech some of the minerals out of the horn, but I'm just guessing on this.