This is half a horse's skull I was given by a lovely lady at Shepreth wildlife park
(it was tiger food)
I've had it in a tub of water with washing powder for the last few months trying to get it nice and clean, using a process called cold water maceration. It hasn't been the nicest job but the end is now in sight. A couple more water changes and it should be ready to bleach.
I may just leave it white or I've been researching bone carving...