I'm going to be making at least one custom knife useing shed antlers I found around my house. I've seen old antlers on the side of a barn that started cracking badly, what should be done to preserve antlers to look good for years to come?

There seems to be a lot of info in the first three results here..

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LMAO! nice one!....Are they on a knife perhaps? Well, deer antlers are like fingernail material. On my antique (1865) bowie I put the handle into a baggie of mineral oil overnight to keep it from hardening up and cracking, which it will eventually fall off if it doesn't. It does not hurt the metal at all either and it looks good as when I got it 25 years later.

Been using deer and elk for years without any problems.  I have a material called resinol that I soak them in now and it helps stabilize them.  Some of the nicest handles I have done were from a set of old weathered elk I got from a guy down the street.  They were all cracked and bleached white.  I filled the cracks with black super glue and it really made them look sweet.  The mineral oil will help also but I have not needed it as of yet.  But then I also use camelia oil on all my handles which will do the same thing as mineral oil.  If you really wanted to stabilize them you can alway send them off to a co that specializes in it.  It can really seal them up and they will be impervious to moisture and oil etc.