Actually, I think they may actually grow synthetic crystals in a special autoclave.
Other than sterilizing things, I'm not sure what you can do with it. I went on Wikipedia and it said that you can vulcanize things and cure resins in one, and some of them pull a vacuum. I don't think the steam would aid in stabilizing stones, however. But you might could figure out some way to pull a vacuum and heat, which might be useful.
I bought some dental equipment a while back and a centrifuge was in the lot. Anybody need to separate a little plasma out of your blood? I really need to find somewhere to sell it, along with all the cad-blanks for crowns.
Debbie K