I have a Longhorn skull that is off a cow that was really really old; I was told 27 years old. The cow finally died and it sat in a field for about 8 months minimum. When the customer brought it to me it had NO meat, hide or hair. It hardly had an odor. I've drilled holes in the back of the horns and funneled some water into them and let them sit bagged up. I've attempted every week to loosen them to no avail. This has been going on for months. My question is could they be legitimately fused together and impossible to get off? At what point do I throw in the towel? Since there is no odor would it be ok to leave them on? I honestly think the bugs in the field it layed in took care of everything. I've thought of funneling borax in the holes I drilled and filling them in. I'm at a loss. I want this beast out of my shop.