Comments by "" (@neutronalchemist3241) on "You Were Right About This" video.

Made in a bloomery, that's what had been used in the west until middle age, what you obtain is a bloom, that, depending on it's position in the furnace, has a carbon content varying from soft iron to cast iron. The bloom is however full of slag and voids and. To eliminate those and obtain a piece of usable metal, it has to be heated and hammered multiple times in a forge. That process eliminates almost all the carbon content. The only reliable way to obtain steel from a bloomery is pattern weld steel. Selecting cast iron parts of the bloom (that tended to pour to the bottom), working those separately from the rest, and finally mixing iron and cast iron bars, bending and hammering them.
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@bakters Err... no. Chinese had blast furnaces since the first century AD. Indians made high quality crucible steel (Wootz steel) since about 5th century BC. In Europe bloomeries were perfected (8th/9th century AD Stückofen, that already allowed to obtain large quantities of homogeneous steel, and so led to the abandonment of pattern weld steel in Europe) until, in XIV century, appeared in Genoa what was later called "Catalan Forge", that directly reduced the mineral. Blast furnaces had been introduced in Europe at the beginning of 18th century. The Eiffel tower is made from blast furnace cast iron puddled into soft iron.
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