I’m getting into this conversation a bit late, but I will give you
my thoughts on your impending project.
Don’t do rhodium plating. It just doesn’t last, and is a terrific
pain if the ring has to be sized (soldered) and then re-plated.
Rhodium has been used to “whiten” the look of nickel alloyed white
gold, which doesn’t look all that white. The idea of going with a
palladium white gold is a good idea. It’s more expensive than the
nickel alloy, but is far whiter and much easier to work with. I have
not had good luck with the palladium alloys I’ve tried, but just
adding 950 palladium to 24K gold ( wear platinum-safe glasses for
the melt) makes an easy working true-white gold. A real pleasure to
roll out, solder and polish.
For all the remarks about the difficulty of working with platinum,
it’s not really that different, but make sure you have no other metal
"contaminants" around where you are working with the platinum,
especially when it is hot. (Platinum used to be used for heating
elements for electric-melt casting machines. When platinum gets
really hot, it melts every other jewelry metal… which can melt onto
and into the platinum if you’re not careful!) Wear your #10 platinum
lenses when melting it or annealing it, and give it plenty of time
when annealing ( I do mine for 2 min., usually). It rolls out
So besides the unusually long time to anneal platinum, and the
cleanliness issues, the final finish can be the most brutal and time
consuming. Many old school jewelers would not reveal their platinum
polishing secrets. It just takes many steps of sanding finer and
finer, special rubber wheels, polishes and burnishers. Be patient,
get as much as you can before you start, and then work
with it! Platinum used to be almost double the price of 24K gold, but
now is only a few hundred more than gold!