 The Romans also exploited the silver present in the argentiferous galena in the mines of Cartagena ("Cartago Nova"), Linares ("Castulo"), Plasenzuela and Azuaga, among many others.Spain was one of the most important mining regions, but all regions of the Roman Empire were exploited.In Great Britain the natives had mined minerals for millennia, but after the Roman conquest, the scale of the operations increased dramatically, as the Romans needed Britannia's resources, especially gold, silver, tin, and lead.