TECHNOLOGY

The Iron Age Begins

~3,000 years ago

History · Iron Age · Holocene · Meghalayan

Ironworking spread about 3,000 years ago, a craft harder than copper's, because iron does not melt in a charcoal hearth and must be hammered out of a spongy bloom.

Early ironworking differs from copper metallurgy by a constraint of process and not only of temperature. Copper melts in a charcoal hearth and can be cast; iron, whose melting point is markedly higher, leaves the bloomery as a spongy mass mixed with slag, called a bloom, which must then be repeatedly hot-forged to expel the slag. Extraction appears to have begun in Anatolia at the start of the second millennium BCE, on a small scale. Analysis of the slags suggests a route of appearance: copper smelters already used iron oxides as a flux, which brought them into contact with the material. Wide diffusion occurs around 3,000 years before present, in the Near East and beyond.

Why it matters

Bronze presupposes bringing together two metals of distinct and scarce origin, hence exchange networks and powers able to control them; iron, whose ore is widely distributed, knows no such constraint. The rhythm of adoption accordingly depends on social as much as technical factors, and is compared region by region and economy by economy.

Dating & uncertainty

The current state of the data supports an Anatolian origin for extraction, on a small scale, at the start of the second millennium BCE; the date retained corresponds to the first major expansion, at the end of the second millennium and the beginning of the first. The hypothesis of an appearance out of copper working rests on the analysis of furnace residues.

Our species’ history as one day

23:46:1713 min 43 s before midnight

if the 315,000 years of Homo sapiens were compressed into a single day