Through acquisitions, such as the Nichols Copper Company, the Calumet and Arizona Mining Company, and the United Verde Copper Company, Cates expanded Phelps-Dodge into an integrated operation in the copper industry. In 1930, the capital stock of Phelps-Dodge was $30 million with 8,000 employees, and sales of $39 million. By 1949, the company’s capital stock was $127 million, assets were $510 million, and employment stood at 15,000.