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Ted Mooney, P.E. RET
Pine Beach, NJ
The authoritative public forum
for Metal Finishing since 1989
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Plating rhodium on white gold (cont'd)
Ed. note; This is an interesting but ridiculously long thread, and only one of many. Before you get too confused, you might want to start with our FAQ on Rhodium Plating and White Gold to get an overall understanding :-)
OK, This may be the DUMBEST QUESTION in the thread, but here goes... I am currently in the throws of a decision to use White Gold or Platinum for my fiancee's solitaire Marquis wedding ring (a D color diamond so I really want a white metal to compliment the stone). The basis of my dilemma is that more than one jeweler has strongly recommended white gold over platinum. They say that platinum looks great at first, but it scratches and they show much more than white gold and the ring will look dull after a year. What about polishing? I asked. Platinum won't polish back up to the original luster, ever, was the answer.
1. Is this an accurate assessment? (here comes the dumb part)
2. Would plating the platinum with a good coating of Rhodium prevent the scratching problem?
A rapid response would be most appreciated as I'd love to present this ring for Christmas.
Thanks in advance for your insights.
Randy M [last name deleted for privacy by Editor]- Seal Beach, California, USA
2001
I would not agree that a ring with the intrinsic value of platinum is ever a problem. A 'white gold' ring would be harder and more scratch resistant because rhodium plating is a very hard surface. But from reading all the responses at finishing.com, you really want a white gold that uses palladium rather than nickel for the white color, and you want a guarantee that any required rhodium replating is covered for some period of time that meets your satisfaction.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2001
Historical enhancement: The second sentence may not be quite true; see Hong Shen' response further into the thread.
This is a professional report; I just happened upon this site and wanted to share this with you all.
I have been a top jewelry craftsman for 40 years. I know exactly what you are all going through, and this is the reason the jewelry business is struggling with this problem. White gold is the poor man's platinum look. Money is the problem, it costs too much to use a good high nickel content to be bright on it's own. Because we can only re-melt the gold 2 times to be safe as the nickel inside the gold becomes very brittle when over heated and gives lots of problems during fabrication. When casting parts we must use more gold than necessary then the scraps (trimmings) are used to melt again for another cast, usually they try to go half used gold with half fresh gold that is to help tenderize the mix so as to try to avoid cracking gold. (Sound familiar) Why do claws fall off a diamond with hardly any force? Some people buy old gold and even dump it in to the pot and pray that it works out. (Not knowing how many times it was melted when it was made say 30 or 40 years ago and then you end up with a patched up mess of a job) Because the gold was melted too many times or was over heated right from the start, that makes the gold brittle, I have seen claws that were holding on by a prayer that I could crack off with my fingernail. It is a big cover up as they know what the problem is but can't afford to use fresh gold every time. The half way effort is to lower the nickel content to tenderize the gold, hence the yellowish white gold that has to be rhodium plated to cover it up. Cartier of Paris started a trend oh 30 years ago where they set their diamonds in 18K yellow gold trying to convince people that it was a style, but I knew exactly what the reason was that they started that. It was to avoid going to white gold, as they didn't always use platinum for cost reasons. You see 18K yellow gold is like butter it never cracks when working with it, it is alloyed with copper and silver, both very soft malleable metals, The nickel used to alloy white gold is the same as in stainless steel that is why it is very hard to work with
The jewelry store sales people would not know anything about this. Platinum is also a big problem these days as every body is casting things they shouldn't be doing, just to follow the trend, a lot of platinum castings are cracking as the metal was not hot enough when cast (Platinum is different it cannot be burnt you could sit on it with a big welding torch for a whole day at over 3,000 degrees and it would only get more pure and more beautiful, But the shops that are out there are greedy as anybody would be and the process to cast items is overloaded by putting too many pieces in each cast. A good cast should not go over 1 or 1 ¡ ounces of platinum to be able to blast the hell out of it so it comes out tender and good to work with. But the society we live in says hey we could get more in and I've known some to go for 3 or 4 ounces at a time, the result is the temperature at the center of the melt is not consistent and by the time the metal gets into the cast some parts are not hot enough and those parts give trouble such as cracking. Hey ! it happened to me too that is how I know. Even small amounts like I did if not heated enough cracked and had to be re processed at a higher heat.
Platinum in it's real use should be hand wrought to be at it's best, but under the pressure of the cost of living short cuts are used. Hey the same goes for the big car makers theses days a lot of junk is out there in the name of cost. Only the rich have the access to the (possibility) of getting the real thing, if they know the right guy that knows what he is doing and not just talking. Walk the walk and talk the talk.
Hope you appreciated my effort, but I cannot change the world alone.
Allan C [last name deleted for privacy by Editor]- Montreal, Quebec, Canada
2001
This is a professional report;
Plating can be controlled by painting nail polish on the parts that you don't want to plate before dipping the item into the Electro plating bath, usually a small beaker [beakers on eBay or Amazon [affil links] the size of a coffee pot is used. Those brown spots are low voltage electric burns likely from several rings at a time on the copper hook in the rhodium bath as the hook is shaken around in the bath to expose all parts to get a good coating. Those burn spots are where the rings shorted out (ouch).
Allan C [last name deleted for privacy by Editor]- Montreal, Quebec, Canada
2001
I've been reading everyone's concerns and want to add my own 2 cents. I am a metallurgist and have been working with precious metals for 12 years.
White gold is a gold alloy (whether 14Kt or 18Kt) that has been rendered white by the addition of an element that whitens gold. There aren't many elements that will make gold white. The most effective is nickel, however many in the population are showing a sensitivity to nickel. the next best is palladium, a platinum group precious metal (remember your periodic table from high school chem!). Platinum will also whiten gold but you need a lot of it. Palladium and platinum are expensive so many people still use nickel to make white gold.
The word "white" can be very subjective and relative. White gold is whiter than yellow gold. However, many times white gold looks dull gray or "dirty" when compared to platinum and silver. This is why many people plate white gold with Rhodium. It is very white and bright and appealing to the eye! It is also very hard. Actually the brightest and whitest metal is silver. But people don't silver plate because it is soft and will tarnish. Rhodium is the next brightest metal, doesn't tarnish and is a platinum group metal, and a very expensive one at that, running about 1700.00 per ounce! This is why many people put a very thin coating that will need replating after a few years. We plate at almost 100 microinches so the plating is very durable and long lasting. When you buy an item, you should be told that it is a plated item because there is the possibility of it wearing off with time and more importantly, if you need the item repaired or sized, or even engraved, the person doing the work needs to know because the plating will get ruined and the item will have to be stripped and replated. Good quality plating should be bright and stain free. Plating will not hide scratches, dents and so forth. If you replate a dull scratchy item, you will get a dull scratchy plating.
Tino V [last name deleted for privacy by Editor]- New York, New York
2002
2002
The feedback from professional jewelers is greatly informative and appreciated. But many problems remain.
First, many people are sensitive to nickel and it's no good to blame the victim anymore; rather, nickel must be removed from white gold formulations. If the industry refuses to do that, the very least we can demand is labelling jewelry that contains nickel.
Second, cufflinks are one thing but heirlooms are another. Engagement and wedding rings are the ultimate heirloom and nobody expects an heirloom to be plated or to require replating in a few months. It is a scandal that a woman can receive an engagement ring that needs replating before her marriage. If someone sues their jeweler for emotional distress, the jeweler better hope that I am not on the jury because I would not consider the suit frivolous :-)
Finally, when the consumer doesn't even have reason to suspect that something is plated, and that the finish is temporary, it is absolutely the obligation of the jeweler to let them know. That isn't happening. The jewelry industry cannot possibly be ignorant of this problem, yet they appear to be making little effort to address it. I pass by jewelry counters all the time and I've yet to see "Rhodium plated" displayed on these rings. That's a critical step we need.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2002
I am an engineering professional who has extensive experience with Nickel, Gold, Copper, Tin, and Chrome platings. After reading this thread, I saw one recent post that really hit on the probable real cause of so many poor Rhodium plating problems on jewelry.
Mr. Volpe correctly stated that the thicker the plating, the more durable it will be. Any Rhodium plating that is at least 95-110 microinches will be extremely durable. In addition, the plating will COVER the base metal completely. People who have 18KT white gold rings that only have a 20 microinch coating are eventually going to see the base metal color "bleed through" as the plating wears or oxidizes over time. Some people in the plating industry may call this thickness a "flash" plating.
Of course, any plating durability is only as good as the process used to apply it. This means pre-polishing, electro-cleaning, acid baths, acid rinses and plating processes are CRITICAL to the performance of the plating (i.e. finish quality, adhesion, color, etc.). As in many other industries, a few jewelry manufacturers keep the expensive plating as thin as possible to keep their profit margin healthy. However, they don't realize that they may be hurting the customer in the long run, especially if the customer is forced to replate an expensive piece of jewelry.
My vote would be to stay away from Rhodium plated 14KT or 18KT product, UNLESS you know that it came from a reputable company, and that the plated thickness is at least 90-100 microinches. If you are NOT confident of the thickness, you can always have it measured at any plating shop that has a X-Ray Fluorescence measuring machine (XRF). This will give you a close measurement of the plating thickness. If it is too low (<50 MicroInches), you will eventually have wear/finish problems - GUARANTEED. I am sure that in the "Old Days" the Rhodium thickness was MORE instead of less.
Larry S [last name deleted for privacy by Editor]- Stamford, Connecticut
2002
I could use some advice on how best to proceed with a White Gold (rhodium plated) problem.
I bought a ring in Dubai (supposedly the best place in the world for gold...) in April 2001. At the time I was only told it was white gold, no plating was ever mentioned. The ring is an engagement ring with a solitaire diamond. By October it had 'normal' coloured gold spots showing through the plating. I have just had it replated and the result was a beautifully brilliant silvery white finish.
It lasted 3 day ! Then the normal gold started to show through on the underside of the shank. (Not against the skin)
It is now back with jewelers for a replating again.
I have worked out that the original problem is likely to be either contamination in the original plating bath or too many rings all being plated together.
The second problem is obviously far too thin a coating of Rhodium from the replating process.
What is the best option for ensuring (insisting that the jeweler put at least 100 microinches of Rhodium on the ring and what justification can I give apart from being a well informed member of the public...?
What is the best way to persuade the jeweler to ensure that the plating is thick enough?
Advice on this would be gratefully received...
My only alternative is to go and get a platinum shank but the other notes here have made me just as worried about that!
Robert M [last name deleted for privacy by Editor]- Reading, Berkshire, UK
A friend of mine told me about that a local jeweler here could dip my ring and make it "so called" platinum. I am very fond of this idea, but want to make sure that is going to be right for me. I am going to get my wedding ring dipped in this rhodium dip per the jeweler and the price is $30 dollars for each ring. That just seems cheap to me and I do not want to get my hopes up and it turn out bad. My wedding ring I hold very dear and just do not want to make a mistake and regret it. I understand because the jeweler told me that of course washing dishes at home in it would not be a good idea (like I do now) and that is ok. I do not sleep in the ring now or do anything that will damage the stones. I would just like a little more insight before I go there this weekend and do this. Please Help !
Thanks,
Etha S [last name deleted for privacy by Editor]- Ardmore, Alabama, United States
2002
Larry from Stamford, CT,
After a ring has a bad rhodium plating can you request from a jeweler a good rhodium plating (100 microinches) over the old and it will work? My ring is 4 weeks old the 3rd day I noticed brown spots and a yellow cast to the entire band. This was a $2000 diamond setting (not including the center stone) and I can't believe it is happening. There are 2 diamond bands that are white gold as well to match the ring and they have not discolored. I do not understand all of this! Does well water that is treated with a water softener which uses salt have anything to do with this?
Please respond.
Lisa D [last name deleted for privacy by Editor]- Brookfield, Ohio, USA
2002
My beautiful wedding and engagement rings were made for me by a reputable goldsmith in white gold. I had requested platinum but she preferred not to use it as she said it was overpriced for little gain. I went with her. My rings did dull, as she warned me they would, but her philosophy is that your rings should wear with you!
After being pregnant my rings needed to be enlarged and so I thought I would get them Rhodium plated as well to bring back some of the original sparkle. This was not done by the original jeweler but by another v.reputable shop. I was warned that their plate could wear off as quickly as 6 months.
6 months have passed and my rings look dull, yellow and scratched....but more worryingly I cannot wear them as my finger looks as if it has been burnt - bright red sores across the top of my finger. I can only assume that the plating has somehow removed a finish my original jeweler applied as this didn't happen before, or only really mildly.
I am off to see the shop tomorrow to see what they suggest.
Also, one of my rings has a band of discoloration down it that I assume is where they enlarged it.
Just go for platinum - nobody I know has ever had a problem with it and I bitterly regret that such important jewelry of mine fell prey to the irregularities of white gold!
Amanda S [last name deleted for privacy by Editor]- London, England
2002
2002
Dear All,
First of all platinum is not white gold. There is no such thing as white gold!
White Gold Alloys with Nickel
White gold alloys became fashionable in the 1920's, mainly as a substitute for platinum, which had itself recently become fashionable. Platinum is quite expensive, needs greater temperatures than gold, and is generally considered harder to work with than gold, although it is ideal for use in diamond settings. At least three patents were issued for different "recipes" of white gold alloys during the 1920's, using different components to produce the whitening or "bleaching" effect. Simply mixing a white and a yellow metal together does not just produce a pale yellow colour, alloying produces a difference in the atomic structure which alters the reflectivity of light of different wavelengths. The commonest metal which causes a significant bleaching effect in gold is nickel, which has the great advantage of being inexpensive, and also providing, in 18 carat alloys, a good colour match for platinum, however its colour matching in 14 and 9 carat alloys is poor. It also has the serious defect that it commonly causes dermatitis, through allergic reactions when worn in contact with the skin. It is also considered to be slightly carcinogenic. E.C. Regulations covering the use of nickel in jewelry are being implemented, and soon all or most new jewelry sold in the Community will have to be nickel-free, or at least "nickel-safe". Most American and Italian white gold alloys use nickel. A typical nickel containing white gold alloy might be, in parts per thousand: Gold 750, Copper 55, Nickel 145, Zinc 50
White Gold Alloys with Palladium
The other metal which is ideal as a constituent of white gold alloys is palladium, which is a close relative of platinum. Its main disadvantage is that it is quite expensive, indeed at the time of writing this, the market price of palladium was higher than that of gold, due to Russian economic and production problems. Its second disadvantage is the high melting point, although jewelry manufacturing and repair equipment has improved, so that most workshops can now cope. A hidden factor in the high cost of alloy components is that there are large proportions of scrap produced during jewelry manufacture. Because this involves expensive precious metal alloys, recycling and reclamation of the precious metals is very important. When scrap contains high levels of expensive metals like palladium, there are extra costs involved in recovering it, which have to be added back to the production costs. Other possible whiteners include silver, platinum, chromium, cobalt, tin, zinc, and indium. Silver would be an ideal constituent, with excellent working properties, but unfortunately it does not have a very great bleaching effect. Copper does not tend to whiten, but is used to improve the ductility of most white gold alloys. A typical palladium containing white gold alloy might be, in parts per thousand: Gold 750, Silver 40, Copper 40, Palladium 170
Dipen Pattni
jeweler/goldsmith - Dar-Es-Salaam, Tanzania
2002
To all,
To apply 2-3 microns of rhodium (80-120 microinches) on a ring is not easy. Typical rhodium plating encounters lots of stress and the plating will peel off from substrate because of stress gradient in the plating. I suspect that jewelers normally don't know how to electroplate gold rings and don't know what thickness is required to prevent underneath nickel to be oxidized, which will make the ring look dull after a while. I suspect by wearing anybody can take the rhodium off even it is too thin. Rhodium is much harder and wear resistant than gold itself. To that matter I don't think palladium alloy will work either palladium will oxidize too if not protected. When I plated rhodium on switch contact we normally got about 0.5-1 µm to get sufficient electrical conductivity and wear resistance.
Rhodium bath is much easier to contaminate and requires lots of control. I bet jewelers just don't have the luxury to do that, such as monitoring specific gravity or organic contamination. If the substrate surface is not activated ( remember it is not pure gold, but a gold, nickel, silver, zinc alloy underneath) the plating itself will also look ugly and have lots of stress.
I doubt the expression that a platinum ring will ding or scratch as platinum has the about the same hardness as rhodium. My advise is buy a gold ring, or if you like the white color, buy a platinum ring, even though platinum is much more expensive.
Hong Shen- Thousand Oaks, California
Hi,
I don't know if it is a language / country-based problem, but I am shocked to read some of the messages below which say that 'white gold' is platinum! Platinum is platinum. It is an element, and if you buy jewelry from a jewelers that is made from platinum it will be referred to as 'platinum'. White Gold is merely gold which has been plated to appear a white / silvery colour - using rhodium. As such, white gold can discolor - my ring came back from being resized much yellower than when I sent it off. But this is a hazard of white gold unfortunately, and as many people have suggested below, the only way to rectify this is to get the metal re-plated with rhodium. It is not a 'con' but one of the facts of white gold. So perhaps people could stop freaking others out by telling them that their white gold jewelry is badly made / cheap / not worth what they've paid for it. If you want the white gold colour in a metal that won't fade then you need to buy platinum, since that is its natural colour - gold is naturally gold colored!
Amy Parker- London, UK
2002
2002
All I know is I had a white gold ring for 17 years, and I wore it continuously, and it never discolored.
So I believe that the ring was an alloy of gold through and through. Plating with another metal does not sound like a good idea for a gold ring.
Tom Pullizzi
Falls Township, Pennsylvania
2002
Okay already, Amy; everyone acknowledged that white gold and platinum are different things 2000 postings ago.
I didn't see anybody freaking anybody else out. I saw hundreds of people expressing dissatisfaction upon buying poorly plated rings, including Robert M whose ring lasted 3 days! When people are terribly dissatisfied with their heirloom because of its low quality, and then they find that it is plated, which they weren't told at the time they bought it, and see that the base material is yellowish rather than the nice white of their grandmother's ring, you bet they are going to complain.
I've been in the plating industry for 35 years; I am a very strong proponent for plating. But jewelers go out of their way to not let the consumer know that these rings are plated and thus have a limited life--sometimes a very limited life. And I sympathize with the people who consider themselves burned.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
To Amy,
I saw lots of people advertising with "Rhodium(platinum)" type of thing. I don't think they are necessarily cheating. Rhodium is not platinum but it belongs to platinum family metals, which consists of silver, gold, platinum, palladium, rhodium, ruthenium, and iridium. If they say it more clearly, such as "rhodium, a platinum family metal" they may actually get away with it.
Hong Shen- Thousand Oaks, California
2002
Thought I'd add my tuppence worth. I do not possess any gold jewelry at all, I dislike the colour. When I got engaged last year I was adamant that I did not want a yellow gold ring. We could not afford platinum so we decided on white gold, not having any idea that it would be plated with anything. I wanted a ring containing an emerald stone (my birthstone) which is more often than not set in yellow gold, so we had to get one specially made.
I had to have the ring replated in October 2002, only 10 months after I had received it. Within three weeks it began to discolour again yet I don't wear it to work and it never even gets wet! I've never had any skin reaction to the ring so based on the above advice I doubt that the plating is reacting to me, it's just poor quality plating. I've read all the above and have decided that I won't bother with gold at all for my wedding ring; I'll stick to the trusty silver that I've worn for years. It never tarnishes as long as it's worn, and I've never even had to clean them.
Helen D [last name deleted for privacy by Editor]- Surbiton, Surrey, England
2003
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