Rhodium plating wears better than the cheaper yellow or colored gold
plating solutions. They will never wear well especially on a ring.
You need to set up a hardened gold plating set up similar to the
plating set up used on watch cases. They use a hardened plating
solution.It has a better wearability factor. They first plate the
object in copper then nickel then gold. The gold is very thin but has
hardeners in the plating solution. It will still not wear all that
well on a ring. A better solution would be to cut out he areas that
your customer wants in white and red gold and weld in the metal
panels of each
Regards J Morley Coyote Ridge Studio