Sometimes customers come to me asking why their gold jewelry suddenly changes color or has white spots, and they are worried that they bought a fake.
In fact, these worries are usually unnecessary. Under normal circumstances, as long as it is purchased from a normal gold store, 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 back on like new.
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 gas 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 have a habit of using skin care products before touching their jewelry, which causes the chemicals to contact the gold directly and cause discoloration of the jewelry. In addition, perfume, hairspray, sea water, pool water, and dirt caused by long-term use 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 above substances and should be cleaned regularly. And if the surface of the gold jewelry has changed color, please don’t use a hard object or tool to eradicate the changed part. The correct approach is to use an alcohol lamp or a welding torch used in jewelry processing to heat the white part of the gold so that the mercury can sublimate from the amalgam and separate from the gold. When the jewelry cools down, brush it lightly with a toothbrush, and then wipe it 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 gas. K Gold and inlaid jewelry does not follow this method, it should 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.