There are several abrasive wheels that can be mounted in your
Foredom which can be used to cut and shape stones with the hardness
There are aluminum oxide cut-off discs that range in size from 7/8"
to 1 1/2" in diameter. They can be mounted on a mandrel in your
There are silicone cut-off discs that range in size from 7/8" to 1"
There are diamond sanding discs that mount on the end of a mandrel.
These have the advantage in that the mandrel screw does not
interfere with sanding.
Check out the catalog of jewelry tool suppliers
The size of stone you can cut and shape into a cab is limited in
the size of disc you use. You can easily cut and shape stones up to
an inch in diameter with the larger cut-off discs.
The process is time consuming and creates a lot of dust unless you
cut under a water drip system. I made a lot of inlay jewelry using
cut-off discs and my Foredom until I bought a rock polisher.
Contact me off line if I can be of specific help in describing the
process. I could send photos of the process.