How did Metallurgy Begin?
There are many riddles connected with ancient metallurgy, starting with how smelting was discovered at all. The campfire theory holds that ores were accidentally used to build stone enclosures around cooking fires, and that people noticed new metals appearing from the ashes. This process may have worked for lead and mercury, which are easily smelted from their ores at low temperatures. However, temperatures are not high enough in campfires to smelt copper, and certainly not iron. Another possibility is that people experimenting with mineral pigments discovered accidentally that they contained metals. This theory is attractive because iron and copper minerals are also brightly-colored natural pigments and it furnishes a likely setting for people to tinker with various methods and observe the results. But the most likely setting to discover smelting is one where high temperatures are routinely applied, preferably under oxygen poor conditions, where ore minerals were likely to be placed,
