The authoritative public forum
  for Metal Finishing since 1989
-----

Prolonging the life of Rhodium plating bath?

Hello,

I am working in Dubai, UAE, in a jewel manufacturing company. As we all know, the marvellous shining on jewellery made of white gold is due to rhodium plating and customers are misguided to understand it as the real finishing of white gold (of course, it raises a question of consumer education!)

Now, after using a rhodium solution for jewellery, we replace the entire solution with that of new one. I would like to have some expert opinions whether it is possible to use a rhodium bath solution for an extended period by adding some replenishers or additives, of course, without causing any problem to the quality of rhodium plating.

Please advise,
Peace.

Sijo Jose
Regulator - Dubai, UAE
2007

---

No, it is not consumer education! True white gold is NOT electroplated! If it is electroplated, that should be stated in readable size print by the MFG and the selling agency.

My white gold wedding ring is gold cut with platinum and possibly cobalt for hardness. PS, it is 47 years old and still shiney.

James Watts
- Navarre, Florida
2007

---

First of two simultaneous responses -- 2007

Jose.
Yes. It is possible to maintain and run a Rh bath continuously. Please take care on following matters.
1.bath should be a considerably big volume say 20-25 ltrs
2.pre-treatment should be extreammely good with no doubts.
3.No carry forward of any, repeat, any impurities.
4.lots of DM water rinses in between.
5.Use rhodium syrup without excess acid for maintenance.
(There are two types available in the market: 1.For make up which have required acid in the syrup/or advise you to add specific qty...2.replenishment syrup or syrup without excess acid.)
Pl. give more details to proceed further!

T.K. Mohan
plating process supplier - Mumbai, India

---

Second of two simultaneous responses -- 2007

Usually when you buy rhodium, it comes in two package.
One for make-up and one for replenisher. As long as you maintain the rhodium bath and not contaminate. It should last for a long time. Contact you supplier and ask for the replenishment schedule. Example, one gram of rhodium for how many amp-minutes. Filter your solution frequently and analyse for the acid & rhodium content. Add as needed.

It has been a practice, even in the fine jewelry trade to rhodium plate precious white metal.

Hamilton Solidum
- Mays Landing, New Jersey