The following description is slightly modified from Assessment Report 21318: "The area of the showing is extensively talus-covered and likely represents a northeast striking shear zone, developed in andesite pyroclastics and siltstones. It is 10 to 15 metres wide and can be traced for approximately 50 metres before being lost in talus cover. The zone is almost completely sericitized and locally silicified with up to 10 per cent disseminated pyrite and pockets of up to 90 per cent massive stibnite, 30 per cent galean, and 50 per cent pyrite. Some boulders indicate that nearby exposures of quartz cemented breccia constitute part of the zone.
Gold analyses ranged from a low of 0.004 ounce per ton to a high of 0.016 ounce per ton in sample #34515. Silver values ranged from 1.5 ounce per ton to a high of 11.7 ounce per ton (#34516). This is likely related to the low base metal content which returned only two anomalous lead values, from samples #34516 (1.55 per cent) and #34515 (1.27 per cent). Sample #34515 is possibly in place while #34516 is float material.
The massive sulphide bodies constitute irregular pods, up to 130 centimetres in diameter with no apparent prevalent attitude, but many of the pods are only partially exposed by trenches, so their full extent remains to be determined. The sulphides include galena, pyrite and stibnite (constituting up to 50 per cent of the pod) with lesser amounts of sphalerite, chalcopyrite and arsenpyrite. In places these minerals are totally oxidized to limonite, manganese-oxides and malachite-azurite. The bulk of the mineralization occurs in strongly fractured to brecciated zones, which occur more frequently in the siltstone unit. The mechanism controlling emplacement of these sulphides bodies is not yet known however it is possible that faults cross cutting the major shear zones acted as ground preparation for ore bearing solutions.
The presence of stibnite as well as very well defined colloform textures in the sulphides (R. Kirkham - personal communication) point to an epithermal origin of the mineralization, although part may have originated in a much higher temperature regime as indicated by the very coarse-grained textures of some of the sulphides.
Copper and zinc values ranged from 0.01 per cent to 0.2 per cent, and 0.01 per cent to 0.39 per cent respectively. Significant lead assays include the following: 6.50 per cent (#34707), 9.47 per cent (#34728), 11.96 per cent (#34726) and 16.30 per cent (#34724). All of the above samples are grab samples of outcrop or subcrop.
Zone C-1, believed to be an extension of Mama Susu-C, is located 300 metres to the south-southwest. The zone consists of several quartz veins up to 50 centimetres wide carrying galena, minor chalcopyrite and abundant manganese stain. The veins are hosted by pyroclastics and sediments and strike north to northeast. Several grab samples collected from the zone assayed anomalous gold values up to 370 parts per billion (#34726). Silver assays returned higher values of 8.99 ounce per ton (#34711), 9.44 ounce per ton (#34726), 12.64 ounce per ton (#34724) and 27.4 ounce per ton (34707). Base metal values were low with a maximum of 0.2 per cent copper (#34707), 16.3 per cent lead (#34724) and 0.39 per cent zinc (#34708)."
According to Open File 1991-21 this showing occurs at or just below the contact between the Unuk River Formation and overlying Betty Creek Formation of the Lower Jurassic Hazelton Group. Fossils found within 100 metres of the showing indicate a Hettangain to Sinemurian age for these rocks.