Natural copper is often interspersed with copper ores, and in the selection of natural copper, the copper ores with higher copper content will be taken together. In addition, natural copper rust green, and some natural ores, such as malachite, blue chalcopyrite and so on are very similar. These similar or dissimilar ores were most likely put into pottery vessels at the same time to be fused. Copper has a melting point of about 1,083 degrees Fahrenheit, whereas malachite and other copper oxide type ores can be reduced by charcoal fire at only about 800 degrees Fahrenheit. Because copper ore is easier to melt than natural copper, so in the process of melting and casting natural red copper, people went on to master the selection of copper ore and smelting, so that the smelting technology in ancient times to a new level. Due to the **** birth of metal ores, a considerable part of the copper smelted by people using copper ore is not very pure red copper, but copper alloy. And people at that time it is impossible to distinguish between a single ore and *** raw ore, and there is no knowledge of alloys, can only note that with different malachite smelting out of the copper in the color of some differences. In this case, people smelt copper alloy unconsciously at the beginning of smelting copper. Furthermore, copper ore is precisely due to the presence of lead, tin, zinc, iron and other components that are born with copper ***, thus lowering the melting point of smelting, smelting out of the copper alloy is much harder than red copper, more suitable for the production of certain tools. In this way, along with the development of copper smelting technology, copper alloy is gradually recognized.

Copper