"Antlers in velvet are a problem in most caribou hunting. Seasons open in August across most of the North, but most bull caribou don't shed their velvet until the first half of September. The antlers vary in hardness throughout this period, and early-season antlers will sometimes be very porous because they're still growing--the reason they're full of blood vessels. The strip-and-submerse solution your guides suggested is most common. The harder the antlers are under their velvet, the better it works. But as you've noticed, stripped antlers don't look like naturally hardened antlers. You can try filling the larger pores with plastic wood, then painting the antlers with a walnut-stain varnish--or take them to a taxidermist who knows how to fix them. You could also leave them outside where the weather will eventually turn them pure white, which doesn't look bad either. The problem with leaving the velvet on is that without some sort of curing it rots. I've heard of various techniques from various taxidermists, but the one that makes the most sense in the bush is to take along a quart of turpentine and a pair of rubber gloves. Squeeze turpentine into the velvet every day for two to three days, forcing the blood out, and the velvet will remain in pretty good shape. I've seen several caribou mounts done this way, and they look good. But the best solution (and the one I prefer) is to go caribou hunting only in September. Even if some bulls are still in velvet, it usually strips off easily, and the antlers are hard underneath. Plus the abundant mosquitoes and blackflies of the North have mostly disappeared. "