|Institution:||Missouri University of Science and Technology|
|Full text PDF:||http://hdl.handle.net/10355/27001|
"The purpose in mind, in writing this thesis, is to select the most economical method of treating the ores found in the Ajo Basin. The ore on the surface, and to a depth of thirty to forty feet, is almost exclusively carbonates in a silicious [six] gangue. Immediately underlying the carbonate ore comes the sulphide ore in its natural state, lying below any action of the elements, and is in various forms. The sulphide has been found in every shaft to its lowest depth" – p. .