Reservoir and slag heaps at the Tharsis mines · Wikimedia Commons (CC BY-SA)

Tharsis Mines

Metalla Tharsensia

MineHispania Baetica · Tharsis, Huelva Province, SpainBuilt 27 BCE · Destroyed 250 CE

About

Augustan-era coins turned up alongside Roman wells and Archimedes-screw drainage systems at this pyrite-belt mine, the second-largest mining basin in Huelva province after Rio Tinto. Slaves worked the galleries in punishing conditions, laboring by lamplight in heat and dust, some spending their entire lives underground turning the tiered water wheels, or noria, that lifted drainage water up through as many as nine levels to an outflow adit. Spain's mines were the empire's single largest silver source, feeding an output that peaked at roughly 200 tons of silver a year across the whole Roman world in the first and second centuries CE. Copper, iron, and silver came out of the same red-stained ground worked here for nineteen more centuries after Rome fell silent. Germanic invasions, not exhaustion, eventually shut the Roman works down.

What happened here

Work goes on underground by lamplight in shifts, and the lamp is also the clock. Galleries follow the ore, propped with timber, drained by wooden screws and bucket wheels worked by hand in stages up the shaft. Ventilation is a second shaft and a fire to draw the air. The labour is convicts, slaves and paid men working side by side on different terms, and the paid men do the skilled cutting. Above ground the ore is crushed, washed in long channels, and smelted, and the smoke kills the vegetation for miles. Mines of any size are imperial property, leased to contractors under written regulations covering shifts, drainage, bath-house charges and who may open a new gallery. Settlements grow around them fast and empty just as fast.