Gold plating mainly appears on gold products such as modeling ornaments. Criminals use copper, lead and other alloys as lining, and the surface is brushed with gold powder. As long as they scrape it lightly with a blade, it is easier for them to see the imitation inside and identify it relatively easily.

In addition, the method of wrapping gold is also one of the fraudulent means, that is, "Li Kui jy" wraps "Gui Li". Take a gold bar as an example. Half of its appearance is pure gold, but the other half wrapped inside is gold with insufficient color. Although they are all gold, the color difference is very large, and it is difficult for ordinary people to distinguish the true from the false with the naked eye. When investors sell, many "Gui Li" can only show their true colors under the detection of professional instruments, but this will undoubtedly greatly reduce the investment value of gold bars.