Thread: Mounting a thin waterstone?

Anything truly quartersawn will be fine. I've mounted stones on cocobolo, cherry, kingwood and walnut. Of those, walnut is the most stable and doesn't need to be quartersawn, I think the others probably really don't, either, only in theory.
Cedar is what is used traditionally on japanese stones, IIRC.

The first and third of that bunch can be skipped, I had them as scrap and they are expensive if they aren't leftovers. Glass, plastic, etc are all fine if you have them and have the means to cut them. you can break the edge on cut glass with silicon carbide paper very easily and it will no longer be dangerous.

I've glued stones with epoxy, silicon sealant and set them in a holder with plaster (for stones that have an irregularly shaped bottom) and all of those worked fine.