It is probably also know as disclosing wax, or touch up wax. Actually
any wax like bee’s wax will do. Just lightly heat the object, and
melt a light covering of wax over the setting area and let it cool.
Then lay your stones in your lay out with the table side down and
mark your spots. TA DAAAA! (I’ve always wanted to say that.) LOL.
P.S. One can use Chap Stick or other lip balms also. Anything to
hold the stones temporarily in the spot to be marked.