The Johnny Lee deposit at Black Butte is named for a homesteader/prospector who lived above the deposit in the early 1900s. The mineral deposit includes two sheet-like zones rich in extremely high-grade copper ore contained in a copper-iron-sulfide mineral (chalcopyrite). It is one of the highest-grade copper deposits currently under development in the world. In fact, it is more than 10 times higher in copper concentration than copper deposits mined by modern surface mining methods.