Discovery of Caracoles silver ores in the Atacama

Background. Starting from the Chilean silver rush in the 1830s, the Atacama Desert was prospected and populated by Chileans. Bolivia and Chile had long disputed the coastal territories between approximately the 23° and 24° South parallels, one of several longstanding border conflicts in South America. The Boundary Treaty of 1866 established 24° S, from the Pacific littoral to the eastern limits of Chile, as the mutual boundary. At the time of its official discovery in 1870, the Caracoles district was located in Bolivia.

Discovery. The silver ores of Caracoles were discovered on March 24, 1870, by a Chilean prospecting team led by José Díaz Gana. The team had departed from the port town of Antofagasta. The site evolved rapidly from rudimentary shelters in 1870 to a small hamlet in 1871, marking the beginning of significant mining activity in the area.

Diplomatic Context. The Caracoles discovery occurred in a region of contested Bolivian-Chilean sovereignty. Separately, a nitrate taxation dispute between Bolivia and Chile later became the direct cause of the War of the Pacific, with Peru drawn in through its secret alliance with Bolivia. In February 1878, Bolivia increased taxes on the Chilean mining company Compañía de Salitres y Ferrocarril de Antofagasta, in violation of the Boundary Treaty of 1874, which had prohibited tax increases for mining. Chilean investors in Bolivia feared that dictator Daza would use the war to expropriate their investments. The supplied passages do not connect the Caracoles silver discovery to this taxation dispute.