This folder contains correspondence and other documents relating to mining and ore milling in Canada, Chile, Europe, and New Zealand. Some of the items deal with inquiries about Edison's ore milling and processing machinery. Other documents pertain to ore samples sent to Edison from various sources. Among the correspondents are Osgood S. Wiley, an Edison agent in the United Kingdom who was dismissed in 1889; James Dredge, the coeditor of Engineering; and S. J. Ritchie, a businessman seeking to utilize Edison's ore milling process in Canada.

Approximately 60 percent of the documents have been selected. The following categories of documents have not been selected: routine correspondence regarding foreign mining properties and ore samples sent to Edison for assay; correspondence about Alfred O. Tate's Canadian business dealings with George D. Dickson and W. H. Dean; letters of transmittal; duplicate copies of selected documents.