The Mavis occurrence is located on un-named creek flowing south into Red Tusk Creek on the south western side of Lydia Mountain at an elevation of approximately 1400 metres. The area has been explored in conjunction with the nearby Red Tusk Discovery (MINFILE 092GNW051) occurrence.
The area occurs in the Clowhom pendant, an elongate pendant of Lower Cretaceous Gambier Group volcanic and sedimentary rocks. The pendant is surrounded by quartz diorite/diorite of the Cenozoic-Mesozoic Coast Plutonic Complex and appears to have undergone local hornfelsing, folding and faulting.
The occurrence is underlain by a series of marine sediments and volcanics in a relatively undisturbed sequence of north to northwest- trending and moderately to steeply west-dipping units. Stratigraphic tops also face west. The sedimentary units are composed of cherts and argillites and do not constitute a large portion of the stratigraphy volumetrically, but are important as marker horizons. The cherts are generally massive but occasionally are well laminated. The argillites are frequently hornfelsed, uniformly fine-grained, black pyritic rocks, occasionally containing narrow (10 centimetres or less) beds of semi-massive pyrite/pyrrhotite and rarely sphalerite. The dominant pendant rocks are andesites and include agglomerates, flows and tuffs. The intrusive rocks are diorite to quartz diorite in composition with minor differentiated zones of granodiorite and gabbro.
The volcanic rocks are variable in composition and include basalts, dacites, rhyodacites, rhyolites, massive andesite porphyries and laminated tuffs, and a distinctive fragmental unit. Late mafic dykes cut the stratified sequence and usually strike northeast and dip vertically. Some folding is evident and faulting is randomly distributed, with little or no movement. An altered siliceous horizon trends north across the property and is comprised of a light- grey to grey massive, aphanitic, siliceous, rhyolitic unit with a characteristic chalky white weathering. Prominent foliation and shearing accompanied by quartz veining is present along the entire length of the unit.
Intermediate to felsic volcanics occupy the central portion of the property. The rocks are dacite to rhyodacite in composition and include flows, gritty lapilli tuffs and finely laminated ash tuffs. A fragmental volcanic rock unit (polymictic volcanic breccia) occurs and is composed of crowded, angular to sub-angular, mixed pebble to cobble- sized clasts of tuffs, flows, chert and argillite in a fine- grained, dusty matrix. This unit generally overlies two thin units of andesite agglomerate and tuff, which in turn overlies andesite flows.
The Mavis zone is underlain by andesitic flows, agglomerates or breccias and argillites. Locally, a mineralized zone trends northeast through the andesitic stratigraphy and is up to 3 metres wide and 100 metres long. Mineralization is comprised of disseminations and pods of semi-massive to massive sphalerite, chalcopyrite and galena.
In 1983, a chip sample (R01456) assayed 9.6 grams per tonne silver, 0.220 per cent copper, 0.069 per cent lead and greater than 1.0 per cent zinc, while a grab sample (R01451) assayed 0.355 gram per tonne gold, 13.5 grams per tonne silver, 1.503 per cent copper, 0.054 per cent lead and 0.040 per cent zinc (Assessment Report 12660).
In 1988, 10 rock samples assayed up to 3.87 per cent copper, 2.56 per cent zinc, 1.12 per cent lead, 73.35 grams per tonne silver and 1.33 grams per tonne gold (Assessment Report 18615).
In 1981 and early 1982, the area was prospected and sampled as the Silver Tusk claims. During late 1982 through 1985, Newmont Exploration of Canada completed programs of geological mapping, rock, silt and soil sampling and 12 diamond drill holes, totalling 647.7 metres, on the area as the Red Tusk property. In 1988, Schellex Gold completed a program of prospecting, rock sampling and trenching on the area. In 1995 and 2000, limited programs of heavy mineral stream sediment sampling were completed. In 2003, Red Tusk Resources, on the behalf of Gambier Mining, completed a program of geological mapping and rock, silt and soil sampling. In 2005, the area was prospected as the Iota claim. In 2009, a petrographic analysis was completed on samples collected in 2005.
