Statement of mining costs in the Butte district three months ending June first 1910

The following cost data were compiled from the monthly cost sheets of the several mines, through a period of three months, April, May and June 1910. These figures were obtained from the cost sheets of the Anaconda Copper Mining Co. and are exact in every instance. The scale of wages and the cost of supplies which prevailed during the period that these figures were created were as follows --page 3