Some of us may know that rhodium-plating as something that is carried out on white gold jewellery, although it is a process that is also used on high-grade sterling silver jewellery.
Rhodium plating has a beautiful, bright-white lustre but has many more benefits besides. We'll attempt to illustrate all these benefits of rhodium plating in this article.
What is Rhodium Plating?
Rhodium is a precious metal and is the most expensive precious metal (even more so than gold). An English chemist and physicist, William Hyde Wollaston, when he was trying to purify platinum, discovered it. He also discovered the metal palladium at the same time (a similarly hard, shiny white metal).
It started to be used commercially in the 1930s to electro-plate jewellery and other items because of the scintillating sheen it gave. As it was so expensive it was used to plate item rather than them being made entirely of rhodium. (Jewellers used to use Palladium in jewellery making and we still have some solid palladium wedding bands here).
Rhodium is a very hard metal, but it’s also brittle and very expensive (even more expensive than gold). In fact, Rhodium is the most expensive precious metal. Therefore, it is not used to make entire pieces of jewellery but used, instead, to plate, or encase, other metals.
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Many people know about gold-plated jewellery. Jewellers plated white gold and some silver jewellery with rhodium. A more recent occurrence is for some jewellery brands to rhodium-plate brass in their designs.
But why do we rhodium-plate some jewellery items?
Why Do We Rhodium Plate Some Jewellery?
1. For Protection
Because rhodium is a very hard metal, it is perfect for protecting another precious metal underneath, which may otherwise show knocks or scratches.
2. It's Hypo-Allergenic
As rhodium is an inert metal, it doesn’t contain any components likely to cause irritation. Therefore, a protective layer of rhodium will help if you are allergic to the metal underneath.
Some people are even sensitive to a precious metal like silver, therefore rhodium can help form a barrier between you and the irritant.
Indeed, it is not an uncommon problem to have a ring that will suddenly irritate your skin.
I have had several customers come in wondering if the ring they have worn for years has suddenly caused a dermatitis-like irritation on one of their fingers. Indeed, this happened to me as I reached middle age - one of my fingers developed a dermatitis-type itchy rash where I'd worn two rings for decades. Our bodies change and we can suddenly react to jewellery we’ve happily worn for years. Sometimes medication can cause our body 'chemistry' to change, our hormones fluctuate and may cause skin sensitivities. It may not be a problem with the metal (my rings were yellow gold, not white). I left the rings off for a time and, luckily, this seemed to cure it and now I never have a problem when I wear them.
If this happens to you, it could be a good idea to try rhodium plating your favourite ring (if made in white gold) and see if it solves the problem.
3. It Doesn't Tarnish
Unlike sterling silver, rhodium doesn’t tarnish (although it wears over years). The reason high-quality silver jewellery brands may rhodium-plate their silver jewellery to keep it tarnish-free, protect it from scratches and give it a high-sheen.
Also, remember whilst sterling silver tarnishes, a quick wipe with a jewellery cleaning cloth will bring silver back to its former glory quickly and effortlessly.
4. To Revamp a White Gold Ring or Piece of Jewellery
Rhodium-plating a piece of old white gold jewellery can be a great idea to revamp it, where it has become worn over the years and looks dull and a little yellowed.
5. Turn a Yellow Gold Item into a White Gold Piece
You can change a yellow gold piece of jewellery to white gold by rhodium plating it. This could be because you are tired of it, or have gone from wearing yellow gold to silver and white gold or it could be that you want to pass it on, but the recipient doesn't wear yellow gold.
I did just this with my yellow gold diamond ring my husband had given me. Whilst I no longer wore the ring I had kept the ring, I didn’t want to dispose of it as it held many wonderful memories for me. Our daughter quite liked the ring but didn’t wear yellow gold. So we had the ring rhodium-plated and gave it to her on her 21st birthday.
It looked absolutely fantastic afterwards and really modernised it. She now loves it and wears it all the time.
The Disadvantages of Rhodium-Plating
1. The Slightly Darker Appearance
Whilst it has a high shine and is white, rhodium-plating can still look darker than sterling silver, even to the point of looking a little grey against sterling silver.
Therefore, some customers don’t like the appearance of rhodium-plated sterling silver.
2. It Wears Off Over Time
Jewellery pieces that are subjected to more ‘wear’ such as rings or chains will require periodic re-plating where the layer of rhodium-plating will eventually come off.
This shouldn’t be too frequent - maybe every five years, with a ring. The 'harder' you are on the ring, the more frequently it will need re-plating.
A white gold ring if the rhodium has worn through may cause irritation to the wearer. By rhodium plating your piece of jewellery again, it will look as good as it did when it was new.
3. The Cost
Because of rhodium plating's rarity, they extract roughly a tenth of the amount each year than gold (around 30 metric tonnes compared to over 3,000 metric tonnes of gold). South Africa is the area that mines rhodium, and this has been prone to problems during the extraction, such as power cuts, making it unpredictable. There is a high-demand for rhodium in the car industry (used in catalytic converters), therefore creating a high demand.
The Process of Rhodium Plating
The process of Rhodium plating involves electro-plating by hydrolysis.
Electro-plating is where a layer of metal applies to a surface of another metal (or plastic). It involves running an electrical current through a solution (called an electrolyte) which causes the atoms in the solution to split and adhere to the metal of the item of jewellery being plated (the item being the electrode).
The precious metal attracts the rhodium.
Is Rhodium Plating Safe for Items with Gemstones?
As gemstones don’t conduct an electrical current, they won’t attract any rhodium like the metal will.
Gemstones like diamonds, sapphires, and rubies are strong and hardy enough to withstand the electro-plating process. Softer, more fragile, gemstones such as turquoise or emerald may not and your jewellery workshop will know whether these stones should need to be removed prior to rhodium-plating the item of jewellery.
How Much Does Rhodium Plating Cost?
Unfortunately, during the lockdown and subsequent increase in metal prices worldwide, the cost of rhodium increased enormously, and this now costs approximately £55 to rhodium plate a ring. If the item is much bigger or the stones need removing, this will cost more.
Ensuring Rhodium Plating Lasts As Long As Possible
It's only really wear that removes rhodium plating from an item of jewellery so to keep your rhodium-plated jewellery looking good for an extended period will mean removing your jewellery when you carry out heavy tasks or housework. This is particularly the case for rings. If you lift weights, I would advise you to remove your rings before you go to the gym. Alos never dip your rhodium plated jewellery in jewellery cleaning dip (and definitely not a silver dip).
To Sum Up
We hope this has given you an idea about what rhodium-plating does and why it is used in jewellery making, which you may not have considered before.
Do drop us a line in the 'Comments' if you have questions or other ideas around rhodium-plating.
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