Vintage photos of:
November 1942. "Conveyor belts carrying copper ore through a tunnel at the Magna mill of the Utah Copper Company. Its plants at Magna and Arthur in Utah are treating vast quantities of the copper so vital for war purposes." Photo by Andreas Feininger for the Office of War Information. View full size.
October 1942. State School of Mines in Golden, Colorado. "Speed in metallurgical analysis, to match the rapidity with which the nation arms itself, is possible through use of the spectrograph, a marvelous new machine used for study of materials through measurements of the arc of light they emit when heated. The aluminum and magnesium industries, steel companies and foundries use it for quick study of metals. Mines use it for exploration. The spectrograph will yield an analysis of seven elements in 15 minutes, which would require up to four hours by old chemical methods. Students in defense training courses at a famous mining-engineering school listen as an instructor shows them how the machine operates." Photo by Andreas Feininger, Office of War Information. View full size.