This folder contains correspondence relating to mines and ores to be bought, sold, worked, or tested. Some of the items deal with the mining interests of individuals and companies who wanted to lease or sell property to Edison or to have their ores tested. Also included are letters by Arthur E. Jenks, secretary and treasurer of the Sapphire Valley Co., and his brother, W. J. Jenks, regarding corundum ore; and a letter by John A. Edman, superintendent of the Diadem Mining Co., concerning gold ore. Most of the selected items received a significant response from Edison.

Approximately 20 percent of the documents have been selected. Some of the unselected letters contain marginal notes by Edison requesting samples of ores, indicating that he will send a surveyor to the property, or giving notice that a survey showed the mine to be unsuitable.