Sometimes clients come to me and ask why their gold jewelry suddenly changes color or has white spots, and they are concerned that they have bought a fake.
In fact, these worries are usually unnecessary. Under normal circumstances, as long as it is purchased from a normal gold shop, the quality of gold jewelry is guaranteed. After a little jewelry cleaning by a gold shop staff, the white spots on the gold will disappear and the jewelry will turn like new again.
Why would this happen? How does gold jewelry turn white? Gold is one of the most stable metals in nature and does not react with any oxide gases in air at room temperature, nor with the three main acids (sulfuric acid, nitric acid, hydrochloric acid) or weak acid. Only aqua regia (a mixture of hydrochloric and nitric acid) can corrode it. But mercury is an exception, it is very easy to react with gold and produce a white compound called amalgam. Therefore, once gold jewelry is exposed to mercury, it will immediately turn white. And because mercury is volatile, it can cause gold to discolor even from a distance.
This can happen in the home, because mercury or mercury-like substances exist in many detergents, cosmetics, and skin care products. If gold is exposed to these elements, it is likely to change color and turn white, gray or dark. Many women are in the habit of using skin care products before touching their jewelry, which causes the chemicals to come in contact with the gold directly and cause discoloration of the jewelry. In addition, perfume, hairspray, seawater, pool water, and dirt caused by long-term wear can also cause gold jewelry to change color or fade. This has nothing to do with the purity of the gold and does not mean that the jewelry is fake.
Gold jewelry should avoid direct exposure to the substances mentioned and should be cleaned regularly. And if the surface of the gold jewelry has changed color, please do not use a hard object or tool to eradicate the changed part. The correct approach is to use a spirit lamp or a soldering torch used in jewelry processing to heat the white part of the gold so that the mercury can sublime out of the amalgam and separate from the gold. When the jewelry cools down, brush it lightly with a toothbrush, and then clean and press it hard a few times with a soft cloth, after which the gold will regain its color. But do not try to do this with a lighter, because the jewelry will easily turn black due to incomplete combustion of the gas. K Gold and inlaid jewelry do not follow this method, they must be taken to the gold shop for other proper treatment. However, if consumers have doubts about the quality of their jewelry, they should go to the professional department and identify the jewelry as soon as possible.