Archaeological data show that early bronzes in China were discovered around 2000 BC. The earliest smelting and use of iron was in the sixth and seventh centuries BC.

Metals did not suddenly appear in some social innovation and leap forward. They gradually entered human civilization during the transitional period between the Stone Age and the Metal Age. Marx once said that as long as you know what metal a nation uses to make its own weapons, utensils and decorations, you can determine its cultural level in a speculative way. The sequence of human discovery and use of metals indicates the degree of human civilization to a certain extent.

Copper: One of the earliest metals used by human beings. As early as prehistoric times, people began to dig dew.