What are the characteristics of natural red copper?

Generally speaking, the purity of natural red copper is quite high, mostly containing only trace amounts of tin, lead, antimony, nickel and other metal impurities.

The pure copper smelted by the original technology often contains not only more metal elements associated with copper ore, such as lead, tin, zinc, iron and so on. And because the smelting temperature is not high enough, copper and slag can not be separated well, so that there will be silicon, calcium, magnesium, aluminum and other oxides.