To be clear, mining it is just the start. I’m no history major but I know a lot about metalworking. I would probably have guessed a quarter of the figure you gave because of that.
Their furnaces could only get so hot, and even if they managed to melt the iron it would dissolve large amounts of carbon from the fuel, becoming pig iron. Much later (19th century) Henry Bessemer invented a way to turn useless pig iron back into steel, but they couldn’t, and without knowledge of the the elements involved had no reason to think it was even possible.
Instead, they would expose a batch of ore to a hot, reducing atmosphere while keeping it solid. Besides being highly fuel inefficient and preventing them from easily using fluxes to purify the metal at the source, this resulted in a bloom, which is beads of iron interspersed inside useless slag. Then, you have to knead the slag slowly, gradually out of the thing by hand. A trip hammer is indeed a big help here, but it’s still a manual process, and the ingot still needs to be reheated many times. Eventually it has a small enough amount of slag to use for tool building, although wrought iron always has some, and has a sort of grain or directionality as a result.
I’d include all the associated lumberjacking and coal and peat mining in the total employment to support this, as well as ore miners, charcoalers, furnace operators and smiths. Global steel production is around 250kg/person today, but obviously that’s an apples to oranges comparison.
To be clear, mining it is just the start. I’m no history major but I know a lot about metalworking. I would probably have guessed a quarter of the figure you gave because of that.
Their furnaces could only get so hot, and even if they managed to melt the iron it would dissolve large amounts of carbon from the fuel, becoming pig iron. Much later (19th century) Henry Bessemer invented a way to turn useless pig iron back into steel, but they couldn’t, and without knowledge of the the elements involved had no reason to think it was even possible.
Instead, they would expose a batch of ore to a hot, reducing atmosphere while keeping it solid. Besides being highly fuel inefficient and preventing them from easily using fluxes to purify the metal at the source, this resulted in a bloom, which is beads of iron interspersed inside useless slag. Then, you have to knead the slag slowly, gradually out of the thing by hand. A trip hammer is indeed a big help here, but it’s still a manual process, and the ingot still needs to be reheated many times. Eventually it has a small enough amount of slag to use for tool building, although wrought iron always has some, and has a sort of grain or directionality as a result.
I’d include all the associated lumberjacking and coal and peat mining in the total employment to support this, as well as ore miners, charcoalers, furnace operators and smiths. Global steel production is around 250kg/person today, but obviously that’s an apples to oranges comparison.