Roger Stern graduated from San Diego State University in 1938 with a B.S. in Physics. He served in the U.S. Navy in the field of Aviation Electronics from December 1944 to March 1946. Roger Stern married Caroline Vota Stern; they had 3 children. His extensive career in the mineral industry spanned more than 40 years. He began as an assayer-metallurgist and superintendent at the El Fenomeno Mine before working for American Smelting and Refining Company in various lead-zinc operations in Mexico.

In 1955, Stern resigned from ASARCO to accept the position of Chief Metallurgist with Cananea Consolidated Copper Company in Sonora, Mexico, also known as Compañia Minera de Cananea. During his twenty-two years with the company, he held various positions, and retired on September 30, 1977, as Assistant General Manager. Following his retirement, Stern acted as a consultant for Pincock, Allen and Holt, a mining industry consulting company in Tucson, Arizona. His expertise was in the fields of mineral dressing, flotation, crushing, copper smelting, and fire refining.

Contains biographical information, subject files, reports and printed materials, 1955-1978, relating chiefly to his career as an engineer and manager at Compañia Minera de Cananea in Sonora, Mexico, and as a consultant with the firm Pincock, Allen and Holt in Tucson, Arizona.

The majority of the alphabetically arranged files reflect topics concerning copper mining operations in Cananea, Mexico. Each file may contain correspondence, memorandum, research notes, blueprints, or printed materials from administrators, researchers, or suppliers to Stern relating to various processes and products in the mine. The major departments of the mine were Open Pit Mining, Concentrator, Leaching and Precipitation, and Smelting; support facilities included power genera-tion, shops, and railroad.

Some materials in Spanish.