GemologyOnline.com
https://www.gemologyonline.com/Forum/phpBB2/

what is rhodium plated silver?
https://www.gemologyonline.com/Forum/phpBB2/viewtopic.php?f=38&t=12593
Page 1 of 2

Author:  bhavatmaj [ Sat Oct 30, 2010 9:30 am ]
Post subject:  what is rhodium plated silver?

what is rhodium plated silver?, and why do they do rhodium plating

Author:  George Sharen [ Sat Oct 30, 2010 10:03 am ]
Post subject:  Re: what is rhodium plated silver?

Rhodium plated silver is sterling silver that has been eletroplated with the metal rhodium

IT is plated for two reasons the main reason is that it doesn't tarnish like sterling
the second is that it looks very much like white gold

hope this helps
wolf

Author:  Barbra Voltaire, FGG [ Sat Oct 30, 2010 10:09 am ]
Post subject:  Re: what is rhodium plated silver?

Rhodium plating on silver works nicely in it's early days, but as the plating wears off ( AND IT WILL: it is only atoms in thickness) the result is a real mess.

The worn parts tarnish, the plated parts do not. The metals have different reflective character....just a mess.

Author:  Kerensky [ Sat Oct 30, 2010 6:04 pm ]
Post subject:  Re: what is rhodium plated silver?

Barbra Voltaire wrote:
Rhodium plating on silver works nicely in it's early days, but as the plating wears off ( AND IT WILL: it is only atoms in thickness) the result is a real mess.

The worn parts tarnish, the plated parts do not. The metals have different reflective character....just a mess.


If you want to have silver (plate or jewellery) either keep it clean the old-fashioned way - or let it tarnish gracefully if appropriate. I first saw Rhodium plating of Silver in Germany in the 1970's and, for sentimental reasons, still have some now. It was 'Yetch' then and it remains 'Yetch' now.

Author:  lyric [ Sun Oct 31, 2010 12:52 am ]
Post subject:  Re: what is rhodium plated silver?

Like Barbra, I am not a big fan of plating in general. It truly does not age well.

Palladium silver or platinum silver will not tarnish as fast nor get as dark as regular sterling silver. No miracle here, but a big difference though, in my experience.

If the budjet is higher palladium 950 (part of the platinum metal group) is very close to platinum in appearance and does not need to be plated.

Author:  Kerensky [ Sun Oct 31, 2010 8:59 am ]
Post subject:  Re: what is rhodium plated silver?

lyric wrote:
Like Barbra, I am not a big fan of plating in general. It truly does not age well.


For electro-plating, I concur. But for Old Sheffield plate I beg to differ. The differences could (and have) filled a book. Old Sheffield is a collectible in its own right and, in terms of workmanship, is sometimes identical (made using the same dies) to solid plate from the shops of the best English smiths of the late Georgian period. Only with the advent of electro-plating did standards of design and manufacture decline disastrously.

Author:  Barbra Voltaire, FGG [ Sun Oct 31, 2010 10:16 am ]
Post subject:  Re: what is rhodium plated silver?

Yes....but we are talking about the commercial plating of sterling silver with rhodium, promoted as a tarnish inhibitor.

When you see it available, pass on the product.
Request unplated sterling.
My 2ยข

Author:  lyric [ Sun Oct 31, 2010 5:08 pm ]
Post subject:  Re: what is rhodium plated silver?

Ditto Barbra!

Author:  Lee Little [ Sat Jan 15, 2011 12:41 pm ]
Post subject:  Re: what is rhodium plated silver?

OK, so I have zero experience with plating so would like to ask some dumb questions.
1) Why is it a mess when the Rhodium plating wears off?
2) Can one simply throw it in the pickle and then re-plate?
3) Is it more of a mess than white gold that has been plated and wears off?
4) Do lots of fans of white gold routinely go back and get a 'new dip'?
5) Couldn't they have saved the money they spent on gold and routinely go back for a 'new dip' on the silver?
Thanks in advance. I only work with 18k yellow and sterling as I do a lot of my own refining and two kinds of dust the same color would only confuse me, however, people ask me about such matters as Rhodium plated silver and even I have no real interest in it, I need to supply educated answers. Best regards, Lee

Author:  Barbra Voltaire, FGG [ Sat Jan 15, 2011 1:02 pm ]
Post subject:  Re: what is rhodium plated silver?

Lee Little wrote:
OK, so I have zero experience with plating so would like to ask some dumb questions.
1) Why is it a mess when the Rhodium plating wears off?
It wears off unevenly, the silver below has a different texture than the plated surface. The exposed silver tarnishes, resembling plaque psoriasis.
2) Can one simply throw it in the pickle and then re-plate?
No, apparently the rhodium has to be removed as well and the cost of replating is greater than the value of the silver.
3) Is it more of a mess than white gold that has been plated and wears off?
Who plates with white gold? Why wouldn't one use rhodium?
4) Do lots of fans of white gold routinely go back and get a 'new dip'?
For jewelry, one would replate with rhodium.
5) Couldn't they have saved the money they spent on gold and routinely go back for a 'new dip' on the silver?

Thanks in advance. I only work with 18k yellow and sterling as I do a lot of my own refining and two kinds of dust the same color would only confuse me, however, people ask me about such matters as Rhodium plated silver and even I have no real interest in it, I need to supply educated answers. Best regards, Lee

Author:  Lee Little [ Sat Jan 15, 2011 1:16 pm ]
Post subject:  Re: what is rhodium plated silver?

Yes, who would plate with white gold?? I meant white gold that was plated with Rhodium.
Thanks Barbara, Lee

Author:  michael_e [ Sat Jan 15, 2011 1:34 pm ]
Post subject:  Re: what is rhodium plated silver?

One of the problems with rhodium plating silver is that it needs a pre-plate with nickel in order to keep from contaminating the rhodium solution, (at least with all of the solutions that I've seen). This double layer would need to be replicated if one was to attempt to re-plate a piece, making it more of a problem than just doing a "quick dip". You also have the problem of making the part an irritant to people that are sensitive to nickel. I think that a person would be better off making their silver pieces in one of the newer non-tarnishing silver alloys, (like Argentium), if they were concerned about tarnishing.

Author:  Lee Little [ Sat Jan 15, 2011 11:09 pm ]
Post subject:  Re: what is rhodium plated silver?

Thanks Michael,
That does sound like a mess. Well, this thread has all the reasons I need to just stay with my policy that I do not plate anything. Keep it simple. Best regards, Lee

Author:  Hans Meevis [ Sun Jan 16, 2011 9:11 pm ]
Post subject:  Re: what is rhodium plated silver?

Quote:
That does sound like a mess. Well, this thread has all the reasons I need to just stay with my policy that I do not plate anything. Keep it simple.


Actually rhodium plating does have a place in jewellery, and silver in particular.
Firstly, to plate rhodium onto silver, one has three options.
1 First copper, then nickle then rhodium.
2 First palladium, then rhodium.
3 Rhodium straight onto silver.
The first two are done in that manner because the rhodium solution is sensitive to copper and will loose its bright plating ability if it is contaminated by base metals.
Particularly copper.
If one plates straight onto silver, then copper (or zinc ) in the silver alloy will, after a short time degrade the solution and the plating will be dark.
The palladium solution is not so sensitive, and will accept silver and keep a high shine, but palladium tends to look more steel gray in colour, so the subsequent rhodium plating brightens the colour up and since no base metals are in contact with the rhodium solution after plating with palladium, it remains stable.
However, all silver will tarnish over time due to the sulphur in the atmosphere. This is a serious problem if the jewellery is in a hot window display for a a few months.
Repeated polishing and cleaning degrades the piece and makes it look second hand and ultimately unsalable.
Also, only rings and bracelets suffer hard wear generally, so earring and pendants will keep their layer of rhodium for many years.
Rhodium is also has a very hard surface, ( much harder than gold and silver ) so it is significantly more wear resistant.
Especially if the layer is not 'flash plated', which is when the piece is plated for ten or twenty seconds.
A well plated ring can last surprisingly long with a thicker layer of rhodium.
I WILL wear off, of course and then indeed, the silver will tarnish to a different colour than the rhodium.
What is often done is to plate areas where polishing or cleaning is not possible after the piece is finished.
So the areas that can be polished or the tarnished removed by a ionic cleaner are left un-plated and recessed areas are plated.
Either with a plating machine or a plating pen.
And just for the record, ALL of the 14 white gold rings that are sold by the commercial jewellery houses are plated to hide the solder marks and the yellow tinge that the ( cheap) white gold has.
So rhodium does have an application in silver jewellery, but when it is thickly plated onto a silver ring, and awear takes place orn the ring, or it has to be sized, for instance, it does cause grey hairs.

Author:  Lee Little [ Sun Jan 16, 2011 11:59 pm ]
Post subject:  Re: what is rhodium plated silver?

Hi Hans,
Thank you very much for the education.
What is involved in re-plating after the palladium then rhodium option? Is it complicated to plate again once it wears off?
By the way, your work looks great. Nice to see such craftsmanship alive and well in a developed country. Best regards, Lee

Page 1 of 2 All times are UTC - 4 hours
Powered by phpBB © 2000, 2002, 2005, 2007 phpBB Group
http://www.phpbb.com/