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Silver tarnish

2003

Dear sirs,

We have a great problem, We produce silver pendants and after 8 weeks silver is tarnish. We plating silver first by Nickel and then Rhodium J2 but this method is not good. Please tell me your idea about methods :

1- Silver Anti Tarnish --- Rhodium plating
2- Silver Anti Tarnish -- Nickel plating -- Rhodium plating
3- Nickel plating -- Rhodium plating -- Silver anti tarnish
4- Only Rhodium plating
5- Only silver anti tarnish
6- Other ... ?

When we plating only silver with Rhodium J2 bath is dark are this problem ?

Best regards,

F. Massoudi
production - Paris, France

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2003

Several years ago I plated silver parts like tie-pins, buttons, etc with nickel+rhodium. The silver parts were usually mechanically polished to obtain a mirror-like appearance. The procedure was basically following:

1.Ultrasonic cleaning
2.Cathodic cleaning
3.Cyanide copper strike
4.Bright nickel, 10 micrometers
5.Rhodium (Degussa J2), cca 0,2 micrometer
6.Hot rinse in de-mineralized water

There were no problems with tarnishing after a period of time.Yes, sometimes there were tarnished parts immediately after plating, probably because of poor electrical contact in rhodium baths.We used lower concentration of Rh(0,5 - 1,0 g/l) and higher current density than Degussa recommended in their instructions. Before plating I personally inspected all baths(incl. analysis) - they had to be in perfect condition.

FRANTISEK HAAS
glass products - Jablonec n.N. , Czech Republic

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I am surprised you are considering using nickel in your plating scheme. As you know there are very strict rules in the EU about nickel containing jewellery, so I would strongly advise you avoid any process that includes nickel. Rhodium will give a different colour to conventional silver, so you may lose some of the inherent beauty. I would therefore suggest you use an anti-tarnish process.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003

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2003

Rhodium is highly stressed and usually cracked, then the silver migrates right thru the cracks and turns black. A dip in weak Hex Chromate will delay the migration.

A palladium diffusion barrier between the silver and Rhodium would be better.

Robert H Probert
Robert H Probert Technical Services

Garner, North Carolina

Hi !

We are having some problems with tarnishing of silver jewelry like necklaces, etc. aside from rhodium plating, any suggestion? I have heard about the lacquer, but what kind of lacquer is suitable, is spray paint acrylic lacquer advisable?

Thank you !

Jason Ledesma
plating shop - Manila, Philippines
2004

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After reading that question I think that you should do clear tuffcoating which will last longer then rhodium plating also. There is company in USA called Gold Touch [a finishing.com supporting advertiser] they have best small and big system.

Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania
2004

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Dear sirs,

We are seeking a protective method for keeping out our silver jewelry from tarnishing. If you know anything which could help us we would be grateful.

Hess Nej
- Essex, England
2004

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2006

The reason your jewelry is tarnishing is because of the sulfur in the air.
What you need to do is store the jewelry in an air-tight container that has no sulfur in it

I hope I helped answer your question :)

Bridget N.
student - Massachusetts

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May 9, 2009

For Silver ornaments,best will be Clear coating applied by Cathodic Electrodeposition.
PPG Industries has distributors in many countries for such coating.
You can get ornaments coated from job coaters.

P B Deshmukh
- Mumbai, India