Ok, I've seen some pretty egregious scientific errors in anime, but I've never seen "bronze ore" before. To clarify, bronze is not found naturally in nature neither as a metal nor an ore because bronze is an alloy of tin and copper in a specific 12% tin 88% copper ratio, it is exclusively produced artificially. it's extremely rare even to find tin and copper veins geographically close to one another, the notable exception being Greece which is in large part the reason why ancient Greece was so prosperous in the bronze age. I know it's kinda silly to get worked up about it in a fantasy setting, but it kinda breaks the immersion for someone like me, and i think it contributes to brain-rot in the less informed. Apologies for the rant, I hope this helps in some way.