This folder contains correspondence and other documents relating to mining and ore milling in Canada, South Africa, Sweden, and Venezuela. Included are documents pertaining to ore samples sent to Edison and offers to sell or rent mining properties to him. There is also a letter by T. Forster Brown containing an extensive report on magnetic iron ore resources in various regions of the world.

Approximately 50 percent of the documents have been selected. The following documents have not been selected: routine correspondence, with no significant reply, relating to offers to sell or buy mining properties.