Thanks colt.
Thanks, it's dye actually and the seat got a coat of bag kote first, added some hi-liter to bring out the cuts better, added a coat of tan kote and will be sealed/conditioned with a custom made conditioner I got from leatherisfun to protect it from UV rays and water.
I'm guessing the skull will still darken naturally and should give it this gentle worn style in time. Probably not as fast as if it would be mounted to a bike, but it should work out fine.