These cookies are absolutely essential for our website to function properly.
We use Google Analytics to measure how you use the website so we can improve it based on user needs.
These cookies may be set by third party websites and do things like measure how you view YouTube videos.
Typed in black ink on cream paper. 14 pages stapled together. Title: 'Methods of Concentration of Minnesota Iron Ores Investigated by the Minnesota School of Mines'. Dated 1st January 1932.
