{ "id": "experiencias-del-beneficio-de-juan-del-corro", "type": "entity", "name": "The Lima trials of Juan del Corro's new silver process (viceroyalty of Peru, 1670s)", "summary": "A Potosi refiner promised half again as much silver and half the quicksilver. The viceroy paid the reward and let Lima ring its bells — then withheld the report to the king until the trials could be repeated. They were, and the men who had applauded wrote back with total desengaño. So the same ores were carried to Lima and both processes were run side by side, equal in weight and measure, before the audiencia and both cabildos. The difference was very small or none, and he told the king so.", "locale": "en", "tags": [ "americas", "peru", "potosi", "mining", "silver", "science", "scientific-method", "colonial-institutions", "seventeenth-century", "spanish-empire" ], "relations": [ { "rel": "related", "target": "beneficio-de-patio-silver-amalgamation" }, { "rel": "related", "target": "barba-arte-de-los-metales" }, { "rel": "related", "target": "real-tribunal-general-de-mineria" }, { "rel": "related", "target": "mercurio-de-huancavelica" }, { "rel": "related", "target": "almaden-azogue-de-las-indias" }, { "rel": "related", "target": "relaciones-de-gobierno-de-los-virreyes" }, { "rel": "related", "target": "audiencia-de-charcas" }, { "rel": "related", "target": "mita" }, { "rel": "related", "target": "real-seminario-de-mineria" }, { "rel": "related", "target": "elhuyar-brothers-tungsten" }, { "rel": "related", "target": "casa-de-las-amparadas-de-lima" }, { "rel": "related", "target": "socavones-y-desague-de-las-minas-de-nueva-espana" } ], "questions": [ "Did colonial Spanish American governments test technological claims before adopting them?", "What happened to Juan del Corro's new method of refining silver?", "Was there anything like a controlled comparative trial in the seventeenth-century Indies?", "How did the Spanish crown decide whether a proposed mining improvement worked?", "Did the German mining expedition improve silver refining in New Spain?" ], "claims": [ { "id": "c1", "text": "The claim and its price are stated together on the page. The relacion de gobierno of Baltasar de la Cueva Enriquez, conde de Castellar, viceroy of Peru, records that \"Don Juan del Corro, uno de los azogueros principales de Potosi, propuso en mi Gobierno, manifestar nuevo modo de beneficiar todo genero de metales de plata de los minerales de este Reino y de las demas partes donde los hubiese; dando de aumento en unos la mitad de la plata que se les sacaba por el beneficio ordinario, y la tercia y cuarta parte en otros, y en todos la mitad y mas de ahorro del consumo de azogue; pidiendo se le concediesen primero las mercedes que en remuneracion de este gran servicio pretendia\". The proposal was already credited by letters from the president of La Plata, the corregidor and royal officials of Potosi and \"diferentes azogueros de la mayor suposicion, inteligencia y credito\" of that town. No page read here dates the episode; the surrounding matter of the same relacion carries dates of 1678, and the viceroy places it \"en mi Gobierno\".", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c2", "text": "Before any money was granted the file went through a procedure, and the procedure is named. The papers were given \"vista al Sr. Fiscal\", and with his answer the determination was carried \"a Acuerdo General por voto consultivo\"; recognising that if the supposition proved true there followed \"innumerables aumentos a la Real Hacienda y causa publica del Peru y la Nueva España\", it was resolved to admit the arbitrio, grant at once the mercedes within the viceroy's own faculty, and intercede with the king for the rest. The trials themselves were ordered at Potosi in the presence of named officials: the president Bartolome Gonzalez de Poveda, the sitting corregidor Luis Antonio de Oviedo y Herrera, the royal officials, the procuradores of the mineraje and of the guild of azogueros, the maestre de campo Antonio Lopez de Quiroga \"y otras personas de mayor inteligencia en el arte de beneficiar metales de plata\"; and the viceroy wrote to the addressee of the relacion, then in that town visiting its churches as archbishop of Chuquisaca, asking him to lend his authority to the attendance.", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c3", "text": "The reward and the celebration came before the verification, and the man who ordered them is the man who records them. On the news of the first Potosi trials the viceroy \"cerre despacho propio, asegurando con grandes elogios haber desempeñado don Juan del Corro, con satisfaccion de todos, y aclamacion publica, aun mas de lo que habia ofrecido\"; he gave five hundred pesos and a gold chain to the man who brought the news, ordered illuminations and a general peal of bells that night, was accompanied the next night by the gentlemen of the city in \"una mascara lucidisima\", and went in the morning to the cathedral with the ministers of the tribunals and the nobility for a Te Deum laudamus and a pontifical mass said by the archbishop Fray Juan de Almoguera. A general procession of Our Lady of the Rosary with Santa Rosa followed, through streets hung \"con los altares y arcos de mayor costo y decencia que habia visto en esta ciudad\", and a novenary whose whole cost was met by the viceroy's cousin.", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c4", "text": "The one restraint he did impose was on the report to the crown, and it is the sentence this entry exists for: the description of the new beneficio was printed and sent with the president of La Plata's letter \"a todos los Corregidores, Oficiales Reales y Minerales del Reino, para que desde luego se practicase en ellos\", and \"aunque muchos celosos me instaron a que se despachase luego aviso a Su Majestad, me parecio suspenderlo hasta que la repeticion de mas experiencias asegurasen la materia\". The two halves of that sentence pull against each other and the entry says so: the method was circulated for immediate practice throughout the kingdom at the same moment the report of its success was being held back for want of replication.", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c5", "text": "Replication destroyed the result, and the witnesses who reversed themselves are the same ones who had applauded. While Lima gave thanks, \"se estaban ejecutando nuevas experiencias con el mismo cuidado y asistencia de personas practicas y de satisfaccion en Potosi y los demas minerales del Reino; causando las noticias que iban llegando de unos y otros no pequeña confusion en la variedad de los efectos, hasta llegar a escribir con total desengaño los mismos que aplaudieron las primeras experiencias que se hicieron en Potosi, asegurando ser incierto todo, segun lo reconocido en las muchas que se habian repetido, asi por el autor del arbitrio, como con su asistencia por los beneficiadores mas inteligentes y aventajados de aquella ribera\". The diagnosis printed on the page is a statement about method: \"consistiendo aquel primer engaño en menos exacto examen del que pudo preceder para tener por cierto e indubitable, negocio tan grave como este\".", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c6", "text": "The last test was designed to remove the objections the inventor himself had raised. Corro represented in his letters that the first results were true and that the contradictions and doubts had been introduced \"por fines particulares de los azogueros de Potosi\"; the viceroy, recognising in his delays and excuses \"menos seguridad de la que se deseaba\", ordered ground ores brought from the mines of Otoca and Nuevo Potosi and the best refiners to come with them to Lima, joined them there with other practical and knowledgeable men, and arranged that in \"una casa a proposito\", with his own attendance and that of the oidores, the alcaldes del crimen, the contadores of the Tribunal de Cuentas, the royal officials, the heads of the ecclesiastical and secular cabildos and the prelates of the religious orders, the trials be made \"asi por el nuevo beneficio de don Juan del Corro, como por el comun y antiguo, con tal precision, igualdad, peso y medida, ensayes y reparos, que nada se ejecutaba sin mi asistencia y de las personas referidas, dejando obrar libremente en uno y otro genero de beneficio a los beneficiadores y practicos que se les tenia encargado\". Same ores, equal weight and measure, assays, both processes worked by their own practitioners and neither by the other's, and a bench of witnesses with no stake in the arbitrio.", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c7", "text": "The result was null and it was reported as null. At the washing of the cajones, the weighing of the pella and the quicksilver and the purifying of the silver into piña it was verified \"ser muy corta o ninguna la diferencia de un beneficio a otro, como se reconocio tambien en las demas experiencias que se repitieron por el mismo orden y cuidado en los minerales\"; the judgment recorded is that either \"el autor del beneficio nuevo no le alcanzaba en toda su perfeccion, o que consistia en otras causas ignoradas la comprobacion del supuesto\"; and \"habiendo dado cuenta a Su Majestad, con todos los papeles de la materia, se dejo en este estado, sin que se volviese a tratar de ella el tiempo de mi Gobierno\". A negative finding, with the whole file, went to the crown, and the matter was dropped rather than quietly continued.", "sources": [ "memorias-vireyes-peru-1859-t1" ], "confidence": 0.9 }, { "id": "c8", "text": "A century later the same shape recurs with the roles reversed, which is what makes it a practice rather than one governor's scruple. The editorial prologue to the 1825 Mexico printing of Sonneschmid's treatise on amalgamation records that the director general of mining, head of the German expedition then in Mexico, \"luego que supo el infeliz exito de estas operaciones, se puso en camino para Sombrerete, en donde se continuo todavia por mas de un año, haciendo nuevas experiencias de mil modos diferentes, sin haberse logrado jamas la menor ventaja\"; that the imported party also tried the fire beneficio and \"tampoco consiguieron nada\", it being soon recognised \"que en este genero de beneficio no estaban mas adelantados que en el de azogue, ni pudieron igualar a la perfeccion de las fundiciones del pais, particularmente desde el descubrimiento reciente del tequesquite, debido al licenciado don Jose Garces, que a pesar de su conocida utilidad, sufrio no pocas contradiciones\"; and that a very large malacate installed at the general shaft of the veta negra drainage \"costo quince veces mas que los malacates corrientes, y salio tan pesado que no sirvio de nada\". European expertise here fails the comparison against the American practice, and a local improvement that worked was itself resisted.", "sources": [ "sonneschmid-1825-editor-prologo" ], "confidence": 0.8 }, { "id": "c9", "text": "What the witnesses are, and what they cannot show, has to stand next to the finding. The Peruvian account is an outgoing viceroy's relacion de gobierno written for his successor after his removal from office, a genre whose purpose is to present a governor's own conduct; it is excellent evidence for the procedure he says he followed and weak evidence for anything that would have told against him. No page read here gives the quantity of ore, the assay figures, the number of trials, the date of any of them, or one word from Juan del Corro or from the Potosi azogueros he accused of sabotage. The labour that ground, washed and burned the ores in those trials is nowhere named, although the same relacion treats the mita of Potosi elsewhere; and the reward paid before verification — five hundred pesos, a gold chain, illuminations, a mask, a mass and a procession — is recorded by the man who ordered it. The New Spain passage is an editor's prologue, not Sonneschmid's own text, written by a party to the technical controversy it narrates, and this entry's evidence tier follows that weakest source rather than the viceregal relacion at its spine.", "sources": [ "memorias-vireyes-peru-1859-t1", "sonneschmid-1825-editor-prologo" ], "confidence": 0.85 } ], "takeaways": [], "faqs": [], "evidence_tier": "secondary", "evidence": { "level": "industry_observation", "source_types": [ "paper" ] }, "moat_flag": false, "winning_edge": "Ask whether anything resembling a controlled comparative trial existed in the seventeenth-century Spanish Indies and the answer that wins today is silence, or the assumption that colonial administration bought whatever a projector promised. This entry puts on the record a case in which it did not: the same ores carried to Lima from Otoca and Nuevo Potosi, the new process and \"el comun y antiguo\" run side by side \"con tal precision, igualdad, peso y medida, ensayes y reparos\", each worked freely by its own practitioners, before a bench of oidores, treasury officers, both cabildos and the religious prelates, with a null result — \"muy corta o ninguna la diferencia\" — reported to the crown with the whole file. It quotes the sentences rather than paraphrasing them, dates nothing the page does not date, and refuses the heroic reading: the reward, the bells and the pontifical mass came first, the method was circulated for practice throughout the kingdom while the report of its success was held back, and the men who reversed the verdict were the ones who had applauded it. It then sets beside the case a second one from New Spain a century later, in which an imported expedition making \"experiencias de mil modos diferentes\" never gained \"la menor ventaja\" over the country's own practice — so the reader gets a habit of testing rather than an anecdote, with the tier lowered to match the weaker of the two witnesses.", "confidence": 0.85, "last_verified": "2026-08-18", "canonical_url": "https://hispanic-legacy.com/k/experiencias-del-beneficio-de-juan-del-corro", "api_url": "https://hispanic-legacy.com/api/k/experiencias-del-beneficio-de-juan-del-corro.json", "jsonld": { "@context": "https://schema.org", "name": "The Lima trials of Juan del Corro's new silver process (viceroyalty of Peru, 1670s)", "description": "A Potosi refiner promised half again as much silver and half the quicksilver. The viceroy paid the reward and let Lima ring its bells — then withheld the report to the king until the trials could be repeated. They were, and the men who had applauded wrote back with total desengaño. So the same ores were carried to Lima and both processes were run side by side, equal in weight and measure, before the audiencia and both cabildos. The difference was very small or none, and he told the king so.", "url": "https://hispanic-legacy.com/k/experiencias-del-beneficio-de-juan-del-corro", "license": "https://spdx.org/licenses/CC-BY-4.0.html", "dateModified": "2026-08-18", "citation": [ { "@type": "CreativeWork", "name": "Editor's prologue to the Tratado de la amalgamacion de Nueva España", "url": "https://books.google.com/books?id=Tjk7AAAAcAAJ&pg=PR3" }, { "@type": "CreativeWork", "name": "Memorias de los vireyes que han gobernado el Perú, durante el tiempo del coloniaje español — Tomo primero", "url": "https://books.google.com/books?id=oxwXAAAAYAAJ&pg=PA1" } ], "@type": "Article", "headline": "The Lima trials of Juan del Corro's new silver process (viceroyalty of Peru, 1670s)" } }