1. Gold is a simple form of chemical element gold, which is a soft, golden yellow and corrosion-resistant precious metal. Gold is a rarer, more precious and more valuable metal. Generally speaking, the gold in the world is in ounces. In ancient China, gold was measured in ounces, which was a very important metal. It is not only a special currency for reserve and investment, but also an important material for jewelry industry, electronics industry, modern communication and aerospace industry.
Second, second to none. It will cause extremely thin gold sheets to roll up easily. Gold weighing 65,438+0 ounces can be hammered down to 65,438+0 _ 4 million and 65,438+000 square _ area. The ancients hammered it into thin slices and threw it into temples and palaces for decoration. All these can show that gold is extremely flexible and plastic.
3. As a precious metal, gold has good physical properties. "Real gold is not afraid of fire" means that gold is not easy to melt under the general flame. High density and heavy touch. Good toughness and ductility, good electrical conductivity. Pure gold is bright yellow, but the color changes greatly after mixing with other metals, such as gold-copper alloy is dark red, and silver-containing alloy is light yellow or grayish white. Gold is easily ground into powder, which is also the reason why gold is dispersed in nature. Pure gold jewelry is also easy to wear and lose weight.
Although gold is a very soft metal, it is not as good as lead and tin. Nails can be used to draw marks on pure gold, which makes gold very easy to process. But this is not ideal for the manufacturers of decorations, because it is easy to scratch the decorations, make them lose their luster and even affect their appearance. Therefore, when gold is used to make jewelry, copper and silver are usually added to improve its hardness.
5. Take gold bars and coins as examples. They all go through melting, tabletting, blank cutting, blank pressing, quenching, acid frying, polishing, pressing, edge pressing and other processes. The working environment of these processes cannot be a vacuum environment. Every link may encounter dust and impurities in the air attached to the blank of the product. These impurities may become erythema after being stored for a period of time without quenching and pickling.