I have a mount that had been hung near a woodstove and also lots of people smoking. Not only were the antlers yellow but the hide also. I used mineral spirits on the antlers and hide both using paper towel and putting the mineral spirits on the paper towel and wiping it down. It took all the yellow completely out and made the mount look brand new again. After it dried I then used furniture polish on the hide and w-d40 on the antlers. It came out amazing.