The GM showing area is underlain by a sequence of marine sedimentary and volcanic rocks of the Upper Stuhini Group. The stratigraphy has been intruded by Early Jurassic monzodioritic to gabbroic plutons. The showing is said to occur in bedded pyroclastic and epiclastic sequences.
Mineralization consists predominantly of pyrite and limonite, supplemented by lesser amounts of magnetite, hematite, chalcopyrite and malachite-azurite. The mineralization occurs in shears and brecciated zones up to several metres wide, along with sericite, calcite, chlorite, and silica alteration. The highest intensity of alteration and mineralization was noted adjacent to rhyodacite dykes crosscutting the formation.
The two highest gold results, 3.36 grams per tonne (#33808) and 170 parts per billion (#33709) come from an east-west trending quartz-pyrite-chalcopyrite vein, 0.5 to 1.0 metre wide, close to the contact with the intrusive (Assessment Report 21177). Copper values range up to 2.62 per cent, silver up to 42 grams per tonne, lead to 0.04 per cent, zinc to 0.16 per cent and arsenic to greater than 2000 parts per million (Assessment Report 21177).
In 1990, Santa Marina Gold Ltd conducted a program on the Arc 18-21 claims that consisted of geological mapping and prospecting in conjunction with geochemical rock sampling (149), limited soil sampling (44) and silt (33) and heavy mineral concentrate (9) sediment sampling. No previous work on the property is documented.
In 2006 and 2007, Hathor Exploration Ltd. completed a 7228.7 line-kilometre airborne geophysical survey on the area as the Snip claims of the Iskut project. In 2008, Max Minerals Ltd. examined the property.