This folder contains correspondence, primarily unsolicited, relating to the procurement and testing of minerals. There are numerous items with perfunctory replies, written by Edison in the form of marginalia, remarking upon his purchasing needs and policies or offering referrals to additional sources of supply and information. Some of the documents pertain to Edison's interest in obtaining metals for possible use in his alkaline storage battery. Additional letters concern his widely publicized idea of making books and other printed material from thinly rolled nickel sheets rather than from wood-pulp paper. Among the correspondents for 1911 is E. Schaaf-Regelman, a dealer in ores and rare minerals. Courtesy of Thomas Edison National Historical Park.