“Old-fashioned” sounds like 20th century vocabulary, but the phenomenon is as old as technology itself. The discovery, around 1450BC, of ways to reduce ferrous oxides to make iron, a material withgreater stiffness, strength, and hardness than any other then available, rendered bronze old-fashioned. Iron was not entirely new;tiny quantities existed as the cores of meteors that had impactedthe Earth. The oxides of iron, by contrast, are widely available,particularly hematite, Fe2O3. Hematite is easily reduced by carbon,although it takes high temperatures, close to 1100°C, to do it. Thistemperature is insufficient to melt iron, so the material producedwas a spongy mass of solid iron intermixed with slag; this wasreheated and hammered to expel the slag and then forged into thedesired shape.
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