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Events/Invention · 1570

Mercury amalgamation adopted for Potosi silver

Invention, early 1570s, Bolivia.

What happened

Mercury amalgamation was first used industrially for silver in New Spain. The Andes adopted it in the early 1570s, using mercury from Huancavelica. Robins and Hagan estimate about 39,000 t of mercury was released as vapour in silver refining at Potosi.1,2

Why it matters

Amalgamation let miners treat poorer ore and drove the output of Potosi, at a high cost in health to the workers.1,2

Story cards

Around the same time

  1. Spaniards find silver at Cerro Rico, Potosi

    UNESCO dates the Spanish discovery of Cerro Rico to 1545.3

  2. A large silver vein is found at Zacatecas

    The 1546 find at Zacatecas started the silver road to Mexico City.4,5

  3. Zacatecas is founded by four Spanish partners

    Oñate, Tolosa, Ibarra and Bañuelos founded the city, and Oñate became one of the richest men in New Spain.4,5

  4. El Camino de la Plata is opened to carry silver

    The road from Zacatecas to Mexico City started to be developed in 1550, with forts against raids.4,6

  5. Legazpi reaches Cebu from Acapulco

    Legazpi left Acapulco with five ships and founded the first Spanish settlement in the Philippines at Cebu.7,8

  6. Manila galleon trade begins

    Manila galleon trade begins.9

  7. Mercury amalgamation adopted for Potosi silver

    Amalgamation let miners treat poorer ore and drove the output of Potosi, at a high cost in health to the workers.1,2

  8. Manila becomes capital of the Spanish Philippines

    Spain settled Manila in 1571, and it became its main trading port in East Asia.7,10

Open the full timeline

Where next

People

Inspired byBartolome de MedinaHis patio process with mercury and horses replaced smelting.11

Mines

Located inCerro Rico de PotosiToledo's mita supplied about 13,000 men a year as amalgamation arrived in the early 1570s.12

Events

Came out ofMercury mining begins at HuancavelicaMercury from Huancavelica made silver refining at Potosi possible.1

Places

Located inPotosiSee the place where this happened: Potosi.1

Sources

  1. Mercury Production and Use in Colonial Andean Silver Production: Emissions and Health Implications (via Europe PMC) Environmental Health Perspectives (Robins and Hagan)
  2. Potosí (item Q35045), coordinate location P625 Wikidata
  3. City of Potosi added to List of World Heritage in Danger UNESCO World Heritage Centre
  4. History and Significance of El Camino Real de Tierra Adentro US National Park Service
  5. Wikidata item Q139242 (Zacatecas)
  6. Wikidata item Q1489 (Mexico City)
  7. Glasinovic Vernon J.P., Revisiting the Manila Galleon, a Chilean Perspective from the XXI Century Latin American Journal of Trade Policy 3 (Universidad de Chile)
  8. Wikidata item Q1467 (Cebu City)
  9. Wikidata item Q683846 (Manila galleon trade begins)
  10. Wikidata item Q1461 (Manila)
  11. Inductees from Mining's Past: Bartolome de Medina Mining Foundation of the Southwest
  12. Potosi entry Encyclopedia.com

Pictures on this page: Bartolomé de Medina (MUNCYT, Eulogia Merle).jpg, Eulogia Merle (CC BY-SA 4.0).

From the Prospector Trails mining history dataset: each fact links to the source it was checked against. Figures are as the source gives them, in the money of their day. Not investment advice.

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Cover photos from Wikimedia Commons: Cerro Rico over Potosí by Jbmurray, CC BY-SA 4.0. Pictures: Potosi, Bolivia, NASA/METI/AIST/Japan Space Systems, and U.S./Japan ASTER Science Team (Public domain (NASA media, no copyright)); South Africa: a crowd of people gathered outside The Goldfields offices in Johannesburg. 1896., Unknown (Wellcome Collection) (Public Domain Mark 1.0); Falu gruva, Lundberg, Bengt A / Europeana (CC0 1.0).