The Sandfury trolls of Zul'Farrak make a tempering agent from sandstones, and I can use that to temper the goods I craft, yes I can! It is highly prized by connoisseurs, so if you bring me a good supply of the temper, then I'll reward you well.
Zul'Farrak is northwest of Gadgetzan. Good luck.
Ah, this is very nice temper indeed! And so much of it! I'll be at work for days before I use it all!