What is rhodium-plated silver?

It is common to see jewelry rhodium plated silver on sale in online jewelry stores.

Unfortunately, Internet users often do not know what this rhodium-plated silver is.

So here is a definition and explanation of what rhodium is and why we use it in jewelry.

Application of rhodium with brush on a wedding ring from our collection

Definition of rhodium plating

Signet ring in 18k rhodium-plated white gold (Vivalatina collection)

THE rhodium jewelry they are rings, chains or bracelets that have been covereda thin layer of rhodiumprecious metal which has the property of protecting silver from the chemical agents responsible for its blackening, i.e. the sulfur compounds present in the air and on the skin.

The thickness of the deposited layer can vary from 1 to 5 microns depending on international standards and the manufacturer. It will be impossible for the buyer to check.

Example of surface treatment using an electrolytic bath (Source: Cookson-clal)

Rhodium is deposited by electrolysis on silver and gold jewelery to protect it from oxidation and maximize its brilliance in light, thanks to the reverberation properties of this metal. This method can be used on all types of silver signet jewelry or rings.

What is rhodium?

On the left, rhodium minerals. On the right, chemical symbol and physical data of the mineral

Rhodium is a rare metal, from the platinum group and extremely expensive, whose discovery dates back to 1803.

We produce around 20 tonnes of it per year worldwide and its price in 2013 was around 30,000 euros per kilo.

We find it only in the mines of the Urals, Canadian Ontario or South Africa. It is mainly used by the automotive industry (90% of global consumption) in catalytic exhaust pipes.

Rhodium-plated silver jewelry is therefore brighter and whiter than classic silver jewelry that interacts with the environment and darkens over time.

However, the rhodium layer is not eternal and deteriorates with friction, rubbing and impact, leaving the silver exposed. The durability of the rhodium layer on a jewel depends on the thickness of the deposit and the care given to the jewel.

Additional cost of a piece of jewelry due to its rhodium layer

Rhodium-plated silver jewelry costs more than classic silver jewelry. The density of this metal is 12.4. Let’s take the example of a simple silver ring measuring 8 and 8 mm wide, with an internal diameter of 19 mm and an external diameter of 21 mm.

The ring has a surface area of ​​1000mm2, therefore a volume of 1mm3 of rhodium to treat the ring with a 1 micron layer of this metal. This corresponds to 0.08 g of this metal which costs almost 30 euros per gram.

Therefore, covering the ring with this precious metal will cost 2.41 euros of rhodium. If the rhodium layer were five microns, it would cost 12 euros worth of rhodium

This calculation does not take into account the industrial cost of the treatment but gives you a idea of ​​the price that rhodium in your jewelry can represent.

What to choose, treated silver or natural silver?

Electronic rhodium plating machine

It depends on your tastes.

THE rhodium treated jewellery They will stay as good as new without maintenance much longer than untreated jewelry.

If, however, you like to keep your jewels and see them evolve over time, seeing them take on different color contrasts depending on the recesses of your jewels, then natural silver jewels will satisfy you completely.

Antique jewelry has thus evolved from a dazzling silver look to a look of tarnished but equally beautiful silver highlights.

If you absolutely want it rhodium plating a jewel in non-rhodium-plated silver in your possession, you can turn to one of the major jewelry brands in France, such as this artisan jeweler from Lyon.

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