This folder contains correspondence and other documents relating to mining and ore milling. Included are letters from the North American Transportation & Trading Co., in which Edison invested, and an accompanying series of notes by Edison regarding gold mining in Nome, Alaska. Also included is a series of letters and reports by geologist Martin Schwerin, who was hired by Edison to prospect for ores in northern Michigan.

Approximately 10 percent of the documents have been selected. Among the documents not selected are letters enclosing ore samples for analysis, requests for information about ore processing, and price quotes relative to drilling through limestone.