The Sphal 5 claim area is underlain by Upper Paleozoic strata of the Stikine Assemblage.
Volcanic rocks observed are purple agglomerates and green tuffs with local, ankeritic shear zones. The mixed sediment unit includes black crystalline limestones and black argillites with interbeds of sandstone. This unit is cut by a major north south structure. The structure hosts quartz ankerite zones containing disseminations and blebs of pyrite, chalcopyrite and tetrahedrite. Grab sample 1336 consists of limey sediment with quartz carbonate veinlets and trace chalcopyrite, pyrite; grab sample 1341 consists of brecciated agglomeratic limestone with chalcopyrite and assayed 0.2 per copper and 112.3 grams per tonne silver (Assessment Report 19197).
Some work was done in 1988 by International Corona but no report is referenced for this. Follow up work in 1989 consisted of the collection of 45 rock samples.