Source: National Bureau of Economic Research  

Release: NBER Macrohistory Database  

Units:  Cents per Pound, Not Seasonally Adjusted

Frequency:  Monthly

Series Has Been Subdivided Into Two Variables: (1)-- Original Data, Lake Copper, 1860-1912; (2)-- Original Data, Electrolyte Copper, 1911-1955. Lake Copper Is From Native Copper Mines Of The Lake Superior District. The Standard Range Of Conductivity Is 99.5%. Electrolyte Copper Is Refined By The Electrolytic Process And Runs From 99.93% And Upwards For Cathodes. Source: 1860-1893:"Mineral Industry", 1893, P.253, And Following Issues; 1894-1955:"Engineering And Mining Journal", January 4, 1896, P. 5, And Following Issues (Also Available In "Mineral Industry" A Supplementary Publication Of "E & M Journal")

This NBER data series m04015a appears on the NBER website in Chapter 4 at http://www.nber.org/databases/macrohistory/contents/chapter04.html.

NBER Indicator: m04015a