From abstract: The North Bradfield River iron prospect is in southeastern Alaska in rugged terrain about 8 miles southwest of the Canadian boundary and about 15 miles northeast of the head of Bradfield Canal. The prospect includes several magnetite-rich ore bodies of pyrometasomatic origin that are localized in skarn. The skarn forms a small part of a northwestward-trending roof pendant that is enclosed in the composite Coast Range batholith. The dominant rocks of the roof pendant are gneiss, granulite, schist, and marble. The ore, which consists almost entirely of magnetite, contains subordinate amounts of hematite, hydrous iron sesquioxides, pyrrhotite, chalcopyrite, and malachite. The ore bodies are crudely stratiform and apparently discontinuous. The largest ore body exposed is traceable for about 350 feet along its strike and averages about 25 feet in thickness. An accurate appraisal of the economic potential of the prospect was precluded by poor outcrops, local snow cover, and inadequate subsurface data.