Rhodium bath: everything you need to know

Is there white gold?

In jewelry stores we are used to seeing white gold with a shiny silver look. What a lot of people don't know is that white gold, as we are used to seeing it, doesn't exist. Did not understand? People explain.

First of all, it is necessary to understand that 18K gold is a alloy which contains 75% pure gold and 25% other metals, which guarantee more resistance to the jewel, since pure gold is an extremely malleable metal. 

In white gold, 75% pure gold is used and another 25% white metals, such as palladium or nickel, for example. Precisely because it is 75% pure gold (naturally yellow), white gold is actually slightly yellow. Oops! Like this?

By adding the 25% whiter metals, we just made the yellow tone of pure gold a little softer and more understated. The more white metals we add to pure gold, the lighter the yellow tone we get.

But you may still be wondering, "why don't we add more than 25% white metals to pure gold to get an almost pure silver color?" Simple: the ratio of 75% pure gold and 25% other metals would be disobeyed, resulting in gold with low purity.

One question still remains: if white gold is, in reality, slightly yellowish, why does it look completely silver in jewelry stores? This is only possible thanks to a finish called rhodium plating or electroplating.

Rhodium bath: what you need to know?

Shine is the word that sums up the rhodium metal curriculum. It is the lining of many jewels made in white gold and is responsible for bringing silver tones to life.

Rhodium was discovered in 1803 by British physician, physicist and chemist William Hyde Wollaston (1766-1828) in crude platinum ores from South Africa. It is a very reflective silver metal, with great resistance to acids and corrosive substances and one of the rarest. Due to its strength and shine, rhodium is widely used in the jewelry industry in the finishing stage.

The 18K white gold alloy, made up of 75% gold and 25% other metals, has a slight grayish-yellow appearance. When the design of a jewel demands a lively and shiny silver, the jeweler bathes the white gold alloy in rhodium. In the case of silver jewelry, which is a relatively soft metal, the bath, in most cases, is given to create a protective layer, since rhodium is the metal of the platinum family that is more resistant to stains and scratches.

It is important to emphasize that the rhodium plating is not eternal. It all depends on the quality of the bath and the thickness of the rhodium layer. Jewelry such as rings and wedding rings are more susceptible to wear than other pieces, as they are used more frequently. Generally, rhodium plating starts to wear out after 1-2 years of use, but in jewelry worn sporadically, signs can appear in the 10s. But rest assured: a new rhodium plating makes the jewelry look like new.

There is also black rhodium plating, which by the way is in fashion. It is a process in which a layer of a dye called brilliant black (dark graphite) is applied to the piece, either by immersion or by selective application. Some materials, such as silver, tin, zinc, aluminum, lead and iron, require an intermediate layer of nickel or gold before applying rhodium, as they are more resistant to corrosion. The preliminary bath prevents the migration of oxidation to the surface of the part.

Remember: as it is a finish, the rhodium plating wears out over time and this is completely natural. However, it is not insensitive to the effects of daily wear and tear and abrasive materials. To limit wear and tear, rhodium-plated jewelry should be avoided when doing household cleaning, gardening and other activities that can quickly destroy rhodium.

And you, are you ready to lavish luxury and wealth with a rhodium-plated jewel? Share your opinion.

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