When recovering gold, it is necessary to remove impurities from it. Generally, a technique called "smelting" is used for refining. First, gold is separated from impurities, and then gold is recovered. In the process of smelting, gold will be dissolved into gas, and then impurities will be extracted according to different melting agents. After smelting is completed, gold will be re-melted into solid, and then it can be recycled.

The color of gold is Huang Chengcheng, similar to golden yellow, with high melting point and strong corrosion resistance, so it can be used to make jewelry, metal products and electronic components. At the same time, because of its high value, it can also be used as precious metals investment.