Black Rhodium Plating
We are marketers of pgm and have had an enquiry about black Rhodium plating.
Can anyone advise how to Black Rhodium Plate jewellery? What products/processes are required?
Johnson Matthey - UK
There are proprietary products for Black Rhodium. Turn to the big suppliers. I know you can find it in UK.
Ed. note: Or turn to the little suppliers too since they seem to be the ones who make possible this site where you are able to post such questions and get answers
We are building this kind of equipment for plating Jewellery, but are You sure about "Black" Rhodium? Or it is Ruthenium ?
- Romano d'Ezz. (VI) Italy
There are a couple of informative patents on the subject:
US 441 6742
US 448 6513
These give reasonable details at the level of patent information.Nahum Finkelstein
- Haifa Israel
November 5, 2008
I just spoke to a plating shop that no longer offers black rhodium plating (even though it's still on their website) because it did not hold up to wear -- they too are looking for an answer. However everyone at the N.Y. JA show who showed it swore it would hold up very well.. what gives?Eve Alfille
- Evanston, Illinois
November 20, 2008
Hi, Eve. I am not a jeweler but I have fielded hundreds of complaints on this site about (white) rhodium plated rings turning yellow, and I suspect the issue is about the same: Rhodium plating is very thin. If it is plated onto a substrate that is the same color, and/or if the plating is on recessed low-wear areas, I suspect it's fine. If it's plated onto a high-wear area of a different color metal, it can't possibly last long.
Ted Mooney, P.E. RET
Brick, New Jersey