History of Ferrous Metallurgy - Iron Smelting and The Iron Age

Iron Smelting and The Iron Age

Iron smelting — the extraction of usable metal from oxidized iron ores — is more difficult than tin and copper smelting. While these metals and their alloys can be cold-worked or melted in relatively simple furnaces (such as the kilns used for pottery) and cast into molds, smelted iron requires hot-working and can be melted only in specially designed furnaces. Thus it is not surprising that humans only mastered the technology of smelted iron after several millennia of bronze metallurgy.

The place and time for the discovery of iron smelting is not known, partly because of the difficulty of distinguishing metal extracted from nickel-containing ores from hot-worked meteoritic iron. The archaeological evidence seems to point to the Middle East area, during the Bronze Age in the 3rd millennium BC. However iron artifacts remained a rarity until the 12th century BC.

The Iron Age is conventionally defined by the widespread use of steel weapons and tools, alongside or in replacement to bronze ones. That transition happened at different times in different places, as the technology spread through the Old World. Mesopotamia was fully into the Iron Age by 900 BC. Although Egypt produced iron artifacts, bronze remained dominant there until the conquest by Assyria in 663 BC. The Iron Age started in Central Europe around 500 BC, and in India and China sometime between 1200 and 500 BC. Around 500 BC, Nubia became a major manufacturer and exporter of iron. This was after being expelled from Egypt by Assyrians, who used iron weapons.