Abstract
The minerals described in this paper are the result of a fire that has been burning in the mine of the United Verde Copper Company, at Jerome, for a number of years. According to Robert E. Tally3 the first fire started in the fall of 1894, on the 300 ft. level, and was the result of a cave in the Hampton ore body. Much of the ore contains abundant pyrite, and the specific gravity of this mineral is high. The collapse of this stope, together with the consequent friction produced by the fragments of ore in settling, may have raised the temperature of lhe mass several degreesl but, undoubtedly, spontaneous combustion was a more important factor in starting the fire. In recent years stripping operations with steam shovels have exposed the still hot rocks impregnated with these minerals