In reference to polishing jade: I’ve mentioned this before on this
forum: John Sinkankas, “Gem Cutting”. This is the most complete,
authoritive work available for all lapidary questions. As has been
mentioned the preparation before polishing is everything. Orange peel
(undercutting) can be mimimalized be using a hard surface to carry
your polishing compound. Cerium is not the best choice for either
nephrite or jadite, two very different materials, usually lumped
together as “jade”. Again, see John Sinkankas. K Kelly