period of abandonment, the mines were rediscovered in 1556 and the Spanish government began operating them once again in 1724. However, Spain's mining operations there were inefficient, and the government itself was otherwise distracted by political and financial crises, leading the government to sell the mines in 1873 at a price later determined to be well below actual value. The purchasers of the mine were led by Hugh Matheson's Matheson and Company, which ultimately formed a syndicate consisting of Deutsche Bank (56% ownership), Matheson (24%) and the civil engineering firm Clark, Punchard and Company (20%). At an auction held by the Spanish government to sell the mine on 14 February 1873, the group won with a bid of GB£3.68 million (ESP 92.8 million). The bid also specified that Spain would permanently relinquish any right to claim royalties on the mine's production. Following purchase of the mine, the syndicate launched the Rio Tinto Company, registering it on 29 March 1873. At the end of the 1880s, control of the firm passed to the Rothschild family, who increased the scale of its mining operations. Operating history Following their purchase of the Rio Tinto Mine, the new ownership constructed a number of new processing facilities, innovated new mining techniques, and expanded mining activities. From 1877 to 1891, the Rio Tinto Mine was the world's leading producer of copper. From 1870 through 1925, the company was inwardly focused on fully exploiting the Rio Tinto Mine, with little attention paid to expansion or exploration activities outside of Spain. The company enjoyed strong financial success until 1914, colluding with other pyrite producers to control market prices. However, World War I and its aftermath effectively eliminated the United States as a viable market for European pyrites, leading to a decline in the firm's prominence. The company's failure to diversify during this period led to the slow decline of the company among the ranks of international mining firms. However, this changed in 1925, when Sir Auckland Geddes succeeded Lord Alfred Milner as chairman. Geddes and the new management team he installed focused on diversification of the company's investment strategy and the introduction of organisational and marketing reforms. Geddes led the company into a series of joint ventures with customers in the development of new technologies, as well as exploration and development of new mines outside of Spain. Between 1925 and 1931, Geddes recruited two directors: JN Buchanan (finance