hey mate
this skull has been boiled and cleaned. then use 50% hydrogen peroxide (which you buy in 20 littres from a cleaning/paint shop). Mix about 20% peroxide and 80% water in a drum. when skull is in there it will fiz, when the fizing dies down (about 12 hrs or longer) take the skull out and hose off (really well) and let dry in the sun. if you leave it in there too long the skull will start to flake. then just coat the skull and horns with some linseed or olive oil.
hope this helps.
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