- or Mexican processThe ore was crushed and ground by mule power in arrastras, reducing it to a fine mud. This was then spread over a courtyard or patio, sprinkled with mercury, salt, and copper sulfate, and mixed by driving mules over it. Chemical reactions caused the silver to dissolve in the mercury. When the amalgamation was complete, the material was agitated with water in large tubs and the mud run off. The amalgam at the bottom was collected and heated to drive off the mercury. Used for much of the world's silver production for 350 years, the process was replaced by the cyanide process early in the 20th century.
* * *also called Mexican processmethod of isolating silver (silver processing) from its ore that was used from the 16th to early in the 20th century; the process was apparently commonly used by Indians in America before the arrival of the Europeans.The silver ore was crushed and ground by mule power in arrastras (arrastra), shallow circular pits paved with stone. Large blocks of stone attached by beams to a central rotating post were dragged around the arrastra, reducing the ore to a fine mud. This was then spread over a courtyard or patio, sprinkled with mercury, salt, and copper sulfate, and mixed by repeatedly driving mules over it. Chemical reactions freed the silver from its compounds and caused it to dissolve in the mercury. When the amalgamation was complete, the material was agitated with water in large tubs and the mud run off. The amalgam remaining at the bottom was collected and heated to drive off the mercury. The process, especially suitable for the silver ores of the dry, barren areas of Mexico, was responsible for a large proportion of the world's silver production for 350 years; it was finally displaced by the cyanide process early in the 20th century.
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Patio process — The patio process was a process used to extract silver from ore. It was developed by Bartolomé Medina in Pachuca, Hidalgo, Mexico in 1557 for the Pachuca Real del Monte mines. The patio process was the first process to use mercury amalgamation to … Wikipedia
patio process — noun : an amalgamation process of reducing silver ore in which ore crushed to pulp is spread on the patio and mixed with salt, copper sulfate, and mercury by spading the mass and driving horses or mules through it … Useful english dictionary
Patio — Pa ti*o (p[aum] t[ e]*[ o]), n. [Sp., a court] (Metal) A paved yard or floor where ores are cleaned and sorted, or where ore, salt, mercury, etc., are trampled by horses, to effect intermixture and amalgamation. [1913 Webster] Note: The patio… … The Collaborative International Dictionary of English
process — processual /pro sesh ooh euhl/ or, esp. Brit, /proh /, adj. /pros es/; esp. Brit. /proh ses/, n., pl. processes /pros es iz, euh siz, euh seez / or, esp. Brit., /proh ses , proh seuh /, v., adj. n. 1. a systematic series of actions directed to… … Universalium
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Medina, Bartolomé de — ▪ Spanish theologian born 1528, Medina de Ríoseco, Spain died 1580, Salamanca Spanish Dominican theologian who developed the patio process for extracting silver (silver processing) from ore. Medina developed the patio process, an… … Universalium
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