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THE NATIONAL GEOGRAPHIC MAGAZINE 



SHEETS OF COPPER READY FOR MELTING 



At this big American copper mine in Chile, plates from the electrolytic tanks, where the 

 copper in solution has been plated onto lead "starting plates," are loaded on cars and carried 

 to the furnaces to be melted. This electrolytic method produces the purest copper. 



Photographs by Richard B. Hoit 



CASTING THE MOLTEN COPPER 



A machine-operated ladle pours the metal into four molds. Each mold contains from 175 to 200 



pounds of 99.6 per cent pure copper. 



