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Black Rhodium Plating
Q. 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?
A. There are proprietary products for Black Rhodium. Turn to the big suppliers. I know you can find it in UK.
chemical process supplier - Israel
A. 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
A. 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
Q. 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
A. 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 millionths of an inch thick. 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 look good for long.
Ted Mooney, P.E. RET
Pine Beach, New Jersey
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