Steel, as we know it, is widely used to build skyscrapers, bridges, and other infrastructure. But there is a long history associated with the production of steel, and the numerous iterations and trial-and-errors it took to perfect the product. Modern steel contains 98-99% of iron, with rest being composed of carbon, which gives steel its tensile strength.
The Chalybes people of the Black Sea were one of the first to try their hand at producing steel around 1800 BC. With the objective to fabricate a metal that was stronger than bronze which could be used to make powerful weapons, they put iron ores into hearths, hammered them, and then heated them so as to soften the metal. The iron present in the weapons that came out of the forge was wrought iron, a predecessor of steel. Even then, their weapons were unmatched by that of any other civilization in the world. The Chalybes later joined the Hittites, forming one of the most powerful armies in the world, with unrivalled weaponry.
The Chinese had fabricated steel’s other cousin, cast iron, around 500 BC. Cast iron was made in furnaces that were seven feet tall. The furnaces were used to burn iron and wood; the resulting product was smelted into a liquid and poured into moulds, which took the shape of statues and cooking tools.
However, neither the Chalybes nor the Chinese were able to produce steel; the composition of both wrought iron and cast iron was not perfect. The Chalybes’ wrought iron contained 0.8% carbon, and the Chinese’s cast iron contained 2-4% carbon. However, the Chalybes moved one step closer to fabricating the desired metal and began to put iron bars amongst piles of white-hot charcoal, which produced steel-coated wrought iron. Little did the world know then that India, a small South Asian country back then, would produce the first pure steel.
The metalworkers in India were able to perfect the ratio of carbon to iron around 400 BC. This was made possible by an invention, a clay crucible. The clay container was used to carry the molten metal; small wrought iron bars and charcoal bits were put into the crucibles, which were sealed and finally put in the furnace. The temperature of the furnace was increased by blowing air from bellows, and the wrought iron melted and absorbed the carbon in the charcoal. After the clay crucibles cooled, what the metalworkers got were ingots of pure steel, which they called wootz steel. Wootz steel was exported all over the world; the Syrians crafted the famous Damascus steel swords, the Spaniards of Toledo made swords for the Roman army.
In Rome, the Ethiopian Empire-based Abyssinian traders played a game of deceit, passing on false information to the Romans that the steel came from a place called Seres (Latin for China). As a result, the Romans were led to believe that the steel came from a distant land that was not possible to conquer. The Romans used this steel, which they called Seric steel to make weapons, equipment for construction, and basic tools.
Gradually, steel replaced iron as the precious metal that people all over the world carried in the form of utensils, tools, and weapons.