After vanquishing the Inca Empire with superior weapons and a touch of treachery, the Spanish conquistadors sought to satisfy their lust for riches by forcing multitudes of native people to toil in silver mines in dire conditions that claimed many lives.
Scientists on Monday described evidence of this bitter chapter of South American history preserved deep in an ice cap in the Peruvian Andes in the form of residue from the relentless clouds of metallic dust spewed from the mines starting in the 16th century.
The mountaintop mines of Potosi in Bolivia were the world's richest silver source.