The Fargo showing area is dominantly underlain by two intrusive units of the Late Triassic-Early Jurassic Iron Mask batholith. Gabbroic to dioritic agmatites of the Iron Mask Hybrid unit underlies most of the western part of the property, while most of the eastern part is underlain by dioritic to syenitic rocks of the Cherry Creek unit. Magnetite is ubiquitous throughout these rocks, ranging from less than 3 per cent in the Cherry Creek unit to more than 10 per cent in the Iron Mask Hybrid unit. Weak to moderate propylitic alteration with attendant pyritization is quite pervasive throughout the Iron Mask Hybrid unit. In contrast, the Cherry Creek unit is pervasively saussuritized with local zones of propylitic, albitic and potassic alteration.
The original Fargo showings consist of quartz veins in diorite of the Cherry Creek unit of the Iron Mask batholith. The principal working is an inclined shaft stated to be 9.1 metres deep with a drift to the north at the bottom. The workings are inaccessible because of water in the shaft (ca. early 1940s). The vein strikes 350 degrees and dips 75 degrees to the west and ranges up to 1.5 metres in width at the collar, tapers to 0.3 metre, and then swells again to 1.5 metres. The best mineralized part is a band about 0.3 metre wide along the hangingwall which contains considerable chalcopyrite and just below, abundant azurite and malachite. The vein has been traced 6 metres south and 3 metres north of the shaft by stripping; both strippings are now sloughed. Another shaft has been sunk at a point 45 metres southwest of the other. It has been sunk 6 metres on a vertical vein that is 35 centimetres wide at the collar and appears to widen near the bottom of the shaft (Geological Survey of Canada Memoir 249).
Extensive percussion drilling by Cominco in 1989, about 600 metres east of the original Fargo showing, indicates that chalcopyrite mineralization appears to occur within an easterly trending, 304 metre wide brecciated zone that contains low grade intercepts that may be spatially related to relatively narrow, steeply dipping, northwesterly and northerly trending fault/shear structures. One hole, PE 89-21, intersected 15 metres grading 0.223 per cent copper. The highest gold value was from drillhole PE 89-32, 0.8 gram per tonne over 3 metres (Assessment Report 18873).
The Fargo group was originally staked and prospected by C.H. King and L.G. Smith. A shipment of one carload of ore grading about 2 per cent copper and 2 grams per tonne gold is reported to have been made. In 1970, Royal Canadian Ventures Ltd. conducted geological mapping, a soil survey (625) and magnetometer survey (38.6 kilometres) on the MR claims which just border the Fargo showing area to the northwest. In 1972, Plaza Resources Ltd. completed a soil survey, ground magnetometer survey and drilled five percussion-drill holes totalling 184.4 metres on the Rose claims. In 1978, Cominco Ltd. completed 7.7 kilometres of induced polarization and magnetometer survey and drilled four vertical percussion-drill holes totalling 245 metres on the Wildrose claim. The drillholes were located about 400 metres east of the Fargo trench showing and intersected only traces of chalcopyrite in Iron Mask Hybrid unit rocks. In 1989, Cominco Ltd. drilled 41 percussion-drill holes totalling 3507 metres on their IM and Wild claims.
Lyra Resources Ltd. drilled two drill holes in 2002.
