> ... and that seems to be a problem because the theory asks us to believe something implausible; that during times of war coin production went down. This does

> ... and that seems to be a problem because the theory asks us to believe something implausible; that during times of war coin production went down. This doesn't really surprise me. Lead production during the first downturn was controlled by the Carthaginians, who were effectively wiped out by the Romans (which is why there was a sharp reduction in lead emissions when the Carthaginian Empire fell, followed by a sharp increase after the Romans restarted lead production). The second and most severe dip happened during the crisis of the third century, which destroyed Roman trade and kicked off the transition from a quasi-market economy to a feudalist economy. The Plague of Justinian happened after the western empire had already collapsed. The eastern empire did control some of the Spanish coast around that time, but it's plausible that mining had already been reduced to a minimum, since most of the Spanish mines were located in what (as far as I can tell) were effectively frontier regions.