Because of its corrosion resistance, permeability, non-flammability and anti-bacteria, copper has a very long service life. Studies have found that Egyptian copper pipes can still be used thousands years ago.
Archaeologists found copper pendants in northern Iraq in 8700 B.C., which glowed with metal despite dust;copper pipe in Egypt's pyramid, which had flowed for five thousand years, was able to flow freely.
Thus, it is precisely because of the unique properties of copper that the sword will last forever. Bronze swords are the best weapons in ancient China. In fact, there are not only swords, but also numerous copper miracles in history.
These historical relics have witnessed the glorious past of copper. In modern times, copper also plays an important role. Copper gutter system, copper doors, copper walls, copper roofs (copper spires) and other copper decorations and buildings,full of ancient feature and unique historical charm.
Over time, they have been oxidized into primitive green, telling about the ancient history.