I was lucky enough to take the only class taught by Michael Dyber a few years ago. Dyber is the first American to win a carving award in Germany.
We used tools that we made from common nails. Shaped with a file and impregnated with Diamond of various grits.
In the photos below you can see the set up he made for us to use with a standard pendant motor we all use in the jewelry industry. There are two black onyx cabochons I carved during the class. There is also a carving of Afghanistan lapis that I carved in a shroud motif. At some point I will gold leaf the carved area of the piece.