I'm no pro, but reading about Roman history they had gigantic mines where they used slaves to extract resources. I think I remember reading that large portions of Spain were mines. In the book SPQR it states that they generated so much pollution from this that the ice in Greenland shows a noticeable increase in pollution around that time (100 BC-ish onwards).
They also conquered so much territory that I'm presuming they took swords/minerals from those regions. Those people would have had their own mines and the Romans now had access to them too.
greenslope t1_j1dgxfv wrote
Reply to How did the Romans manage to arm most of their soldiers with swords? by Horror_in_Vacuum
I'm no pro, but reading about Roman history they had gigantic mines where they used slaves to extract resources. I think I remember reading that large portions of Spain were mines. In the book SPQR it states that they generated so much pollution from this that the ice in Greenland shows a noticeable increase in pollution around that time (100 BC-ish onwards).
They also conquered so much territory that I'm presuming they took swords/minerals from those regions. Those people would have had their own mines and the Romans now had access to them too.