After years of prospecting under great difficulties, alone with his wife in the Bolivian mountains, he saw his tenacity rewarded by the discovery of one of the greatest tin deposits ever known. He was then able to give a free rein to his organizational talents, and within a few years, his mine became the most important in the country, operated using highly modern methods under the direction of the best foreign engineers.

It was the lack of qualified high-ranking personnel in Bolivia that prompted Simón I. Patiño, as far back as 1931, to establish the Simón I. Patiño University Foundation, with the principal object of providing the country with an intellectual elite that would put an end to its dependence on foreign specialists.

Simón I. Patiño then extended his area of operations to other mines and diversified his activities. He founded a bank in Bolivia, marketed his own ore, opened foundries and at the same time invested in ore deposits in Malaysia, Canada and elsewhere. By the end of the 1930s, more than 60% of the world's tin output was being processed at his foundries.

In 1912 he moved with his family to Europe. In 1924, while on a visit to Bolivia, he suffered a severe heart attack which made it impossible for him to return to his country because of its high altitude.

In 1939 he left Europe for New York. Towards the end of his life he settled in Argentina so as to be nearer his home country.

During the two World Wars Simón I. Patiño espoused the cause of the Allies, reserving for them his entire ore output, which was essential to the industrial war effort.

He died in Buenos Aires on 20 April 1947.