The deposit was in the Ironwood Iron Formation, cross-cut by gabbro dikes. Supergene enrichment of iron and manganese minerals was controlled by permeability differences imposed by the dikes. With workings to 5,000 feet, this was the deepest underground iron mine in the world. Powell Kyanite - Kyanite occurs in gneisses and schists in the Powell area, in Sec. Attempts to produce kyanite economically from these outcrops in the 1930's were unsuccessful.
Minerals occur in amygdules, groundmass and veins of basalts.
Tyler's Fork - Metamorphosed Ironwood iron formation.