Key facts

• The Cerro Rico and the silver: the silver veins of the Cerro Rico (first mined in 1545) produced an estimated 45,000 tonnes of silver between 1545 and 1825 — more than the rest of the world’s silver production combined during the same period; the silver was minted at the Casa de la Moneda (the Royal Mint, now a museum) into pieces of eight (the peso de ocho reales) that circulated throughout the Spanish Empire and the Asian trading networks of the Manila Galleon trade; the silver peso of Potosí became the first world currency — the model for the American dollar (whose $ sign derives from the P/S abbreviation for “peso” minted at Potosí) and the basis of the European monetary system through the 17th–18th centuries
• The mita (forced labour): the silver was extracted using the mita — a system of forced labour imposed on the indigenous Andean populations of a vast region (the Viceroyalty of Peru, from present-day Peru, Bolivia, Chile, and Argentina); under the mita system, each indigenous male between 18 and 50 was required to spend one year in seven working in the Cerro Rico mines; the conditions were lethal (mercury poisoning from the amalgamation process, cave-ins, extreme cold at altitude, disease); estimates of deaths vary from 3 to 8 million indigenous Andeans over the colonial period of mining; the saying attributed to Bartolomé Arzáns de Orsúa y Vela (“the Cerro Rico swallowed so many Indians that the mountain of silver became a mountain of bones”) reflects the contemporary recognition of the human cost
• The Casa de la Moneda (Royal Mint): the finest colonial building in Bolivia — a massive stone building (1773, the second mint on the site after the first was demolished as too small; the current building took 24 years to construct) that housed the machinery for rolling and cutting the silver blanks, the engraving workshops, and the administrative offices of the Spanish colonial mint authority; the mint operated from 1773 to 1953; it is now the Museo de la Casa de la Moneda, the most important museum in Bolivia, with collections of colonial silver, colonial painting, and original minting machinery
• Baroque churches: Potosí built 86 churches during its colonial period (one of the highest densities of religious buildings per capita in any city in the world); approximately 25 are still standing in varying states of conservation; the most significant are the Cathedral (1564–1572, rebuilt 19th century), the Iglesia de San Francisco (1547, rebuilt 1726), the Iglesia de Santo Domingo (with its Mestizo-Baroque stone façade), and the Iglesia de San Martín; the churches were built in a distinctive Andean Baroque style (Mestizo Baroque or “Andean Baroque”) that combines Spanish Baroque architecture with indigenous Andean decorative motifs (sun symbols, vegetation, human figures in indigenous dress)
• The Cerro Rico mines (today): the Cerro Rico is still actively mined by approximately 10,000–12,000 cooperative miners (primarily indigenous Quechua and Aymara men) who work in the same tunnels and with approximately the same 16th-century technology (hand drilling, donkeys, and basic ventilation); tourists can enter the active mine with a guide (a controversial but widely offered activity); the miners offer gifts of coca leaves and 95% alcohol to the “El Tío” (the mining devil, a syncretic figure combining pre-colonial Andean earth deities with Christian imagery); the structural integrity of the Cerro Rico has been compromised by centuries of uncontrolled mining and it is now classified as an endangered UNESCO site
• Heritage: UNESCO World Heritage Site, City of Potosí, inscribed 1987 (on the Danger List since 2014)
• GPS: 19.5836° S, 65.7531° W