Although the mother vein of
Guanajuato was discovered in 1548, the Valenciana mine reached its highest production levels from 1768 to 1804. The mine produced 60% of the world silver production in the 18th century. In 1760, the young Antonio de Obregón y Alcocer obtained a loan from the merchant of the Rayas mine, Pedro Luciano Otero. For several years, they both continued investing in the mine until in 1768 their production increased considerably. For several decades, the La Valenciana mine produced more silver than all the mines in the
Viceroyalty of Peru, being Obregon's partners, Messrs. Otero and Diego Rul. On 20 March 1780, the King
Charles III of Spain – at the request of the Viceroy
Antonio María de Bucareli y Ursúa – granted Obregón the titles of Viscount de la Mina and count of La Valenciana, located in Guanajuato, Mexico. In 1788, his son Antonio Alonso de Obregón and de la Barreda succeeded him. Although he inherited the titles, the property of the mine was divided into twenty-four shares, the descendants of Obregón kept ten shares, the family of Otero twelve shares and the family of Juan Antonio de Santa Ana two actions. On 8 August 1803,
Alexander von Humboldt visited the mine, according to his "Political Essay on the Kingdom of New Spain" the mine had "given its owners four hundred to six hundred million pesos, at least, of annual utility." In 1817,
Xavier Mina tried to take the plaza of Guanajuato. When he failed in his objective, he ordered the mine's machinery to be set on fire. From 1848 to 1865, the administration of La Valenciana was in the hands of Francisca Pérez de Gálvez. Towards the end of this cycle, the family company was undercapitalized with several of its mines flooded. In 1865, her nephew Miguel Rul took over the administration, undertaking a rehabilitation process. By selling his agricultural properties, he injected capital into his mining properties. In 1872, he formed the Restorative Company of Valenciana and in 1877 La Concordia to work the mines of Mellado and Rayas. In addition, he invested in other mines of the Casa Rul in Guanajuato. By 1878, La Valenciana was able to produce again the largest volume of silver in Guanajuato, achieving a total of 15,000 tons in 1887. But, the average volume of extraction fell to 5,900 tons between 1885 and 1888. By 1889 only 2,400 tons were extracted. In the decade of 1890, the Mining Negotiation of Casa Rul in Guanajuato was in frank crisis. In addition to the low productivity, the metal price decreased by 40%. When Miguel Rul died in 1897, the administration was led by his widow Mariana Olmedo and his brother-in-law José Olmedo. The Olmedos – who also came from a mining family in the
State of Hidalgo – operated the mines from 1898 to 1904 through the Mining Negotiation of Casa Rul in Guanajuato. In 1900 the production of La Valenciana was reduced by half and continued to lower its extraction volumes during the following three years. In 1904, the Olmedos sold the company to the American company, Guanajuato Reduction and Mines Company. During the
Mexican Revolution most of the mining works were suspended, from 1922 the investment of American capital reactivated this sector. However, the situation changed with the
crisis of 1929 and the decrease in production of the mines registered in Mexico. In 1936, a strike of miners in La Valenciana lasted until 1937. Due to these labor problems and the decrease in productivity, finally, the mine passed into the hands of the workers of section 4 of the National Union of Mining, Metallurgical and Similar Workers of the Mexican Republic, who formed the Cooperativa Minera Metalúrgica Santa Fe de Guanajuato. == San Cayetano Temple of the Confessor ==