Excelsior Mining is developing the Gunnison copper project in Arizona. It is an In-Situ-Recovery (ISR) project and many people including a significant portion of the industry itself are not familiar, or at least not comfortable, with it. ISR involves drilling wells and injecting a dilute acid to dissolve copper from fractured rocks. The pregnant solution is then recovered and standard solvent extraction and electrowinning is used to produce a copper cathode (sheets of nearly-pure copper that are sold directly to manufacturers and therefore no refining is required). Lack of familiarity by the market is usually an opportunity for astute and fearless investors, and it is the case here.