Takarakuji De 40-Oku Atattandakedo Isekai Ni Ijuu Suru - Chapter 41

The author seems to not know that iron weapons were not superior to bronze. For almost 1000 years, bronze and iron were both being used, and bronze was preferred the whole time. Bronze was sharper, easier to maintain, lighter, less likely to break, repairable, and much easier to make. Iron required huge fuel and ore inputs, high temperature furnaces, was prone to shatter in combat, rusted incredibly fast, and if it got damaged it became trash. The only reason iron became dominant is that copper and tin became difficult to obtain.

Part of the confusion is that iron isn’t just another word for steel. Early iron weapons were usually steel, but early steel wasn’t like the steel we know today. I doubt the author realises that, because he thinks vegetable slicers would be cheap and easy to produce. It took a millenium and more to develop really good steel, and making it remained a closely guarded secret for another millennium after that. The idea that Valvert discovered iron in the last 5 years and is only three years away from marching an invincible steel-clad army over the mountains is ridiculous in so many ways. That Valetta the SuperGenius could read a metallurgy book in a foreign language and set up a viable country-wide steel industry in a couple of years is actually the more credible idea.