One thing I learned all those years in the stone restoration business is not hire someone with any experience. If you do , you end up undoing all their bad habits. I would concentrate on someone with a family and someone from another construction trade. I find these are the best employee since they already have hand skills that can easily learn stone restoration. Also they are motivated since it is a new job and they will be learning. As far as wording I would just put together something like.   Learn how to restore marble and granite.  No experience necessary. something like that.  Weed out the ones you don't like with a telephone interview