The Silver Tip property is underlain by a north-northwest trending belt of volcanic and sedimentary rocks of the Lower Jurassic Hazelton Group. The sequence is folded into a syncline whose axial surface trace strikes north-northwest along the west side of Long Lake. The folded sequence is cut by the east-southeast trending Portland Canal dyke swarm of Eocene Age. North trending faults appear to postdate the dykes.
The oldest rocks in the claim area are andesitic tuffs with intercalated argillaceous epiclastics of the Unuk River Formation. Overlying this unit on the east side of Silver Creek is a felsic tuff sequence of the Mount Dilworth Formation dominated by a thick unit of carbonaceous crystal and lithic lapilli tuff with local argillaceous siltstone lenses. This unit is the dominant host rock for mineralization. This is overlain disconformably by dark grey to black grits and ash-rich argillaceous siltstones of the Salmon River Formation.
The Portland Canal dyke swarm trends perpendicular to the volcanic-sedimentary sequence. There are three dyke lithologies. The oldest are biotite or biotite-hornblende granodiorites, which may be up to 60 metres in width. These are crosscut by aphanitic microdiorite dykes which in turn are cut by thin lamprophyre dykes. Aplitic lenses also occur, often associated with quartz veins in mineralized zones.
The main area of mineralization, east of Silver Creek and south of Porphyry Creek, consists of two veins, the May P.J. and Blind veins which have been explored by two adits and two drifts.
The May P.J. vein is continuously exposed underground for about 98 metres, of which 41 metres is mineralized. The eastern underground exposure consists of barren vein-breccia. The vein is lenticular with quartz, calcite, and sulphides cementing black tuff fragments in vein-breccias. Widths vary up to about 0.6 metres with irregular streaks of sulphides up to 0.3 metres across. Mineralization consists of pyrite, galena, chalcopyrite, sphalerite, tetrahedrite, freibergite, pyrargyrite, argentite and native silver. The mineralized zone strikes 120 degrees and dips 35 degrees southwest.
On the surface, the May P.J. vein is represented by the East and West shoots. Based on a continuous 61 metre down dip length and 0.9 metre width, indicated reserves were calculated by Plumb (1957). The West Shoot totals 7485 tonnes grading 34.3 grams per tonne silver, 1.2 per cent lead and 1.5 per cent zinc, based on an average of 11 channel samples. The East Shoot totals 3810 tonnes grading 371.7 grams per tonne silver, 1.7 grams per tonne gold, 3.2 per cent lead and 2.5 per cent zinc. (Plumb, 1957). The combined reserves would be 11295 tonnes grading 148.1 grams per tonne silver, 0.77 grams per tonne gold, 1.9 per cent lead and 1.8 per cent zinc. Assuming the East Shoot to be a high-grade lens measuring 23 by 12 by 1 metres, it would contain 816 tonnes grading 4.8 grams per tonne gold, 970.3 grams per tonne silver, 4.2 per cent lead and 6.2 per cent zinc (Plumb, 1957).
The Blind Vein is south of the May P.J. Vein and strikes west and dips 40 degrees south in the black tuff unit. The vein is faulted along the hangingwall and footwall. Lenticular zones, up to 1.8 metres wide, contain black tuff fragments, fault gouge, quartz, aplitic lenses, graphite, and sulphides. The vein-breccia is exposed for 35 metres underground, of which 30.5 metres is mineralized. Thirteen channel samples across an average width of 0.8 metres averaged 255.8 grams per tonne silver, 0.3 per cent lead, 0.2 per cent zinc, and 1.37 grams per tonne gold (Plumb, 1957).
Several other veins occur on the property. From 1949 to 1951, 22.9 tonnes of ore were shipped, yielding 308.6 grams of gold, 57908.6 grams of silver, 3240 kilograms of lead and 4390 kilograms of zinc (Annual Reports 1950, 1951). A total of 732 metres of underground work and 183 metres of surface diamond has been completed to date.
Work History
The first activity reported was in 1915 when C. Williams shipped a small amount of ore from surface cuts. Three claims, the Silver Leaf, Bella Coola, and May P.J., were owned and under development by J.V. Clegg of Hyder, Alaska, in 1919. The Silver Tip Mining Syndicate, Limited was formed in 1920 but the property fell idle shortly thereafter. Silver Tip Mining Development Company, Limited was formed in May 1925 and development work was carried on until 1929 when operations ceased. The company name was changed in 1946 to Silver Tip Gold Mines, Limited. The property consisted of 5 Crown-granted claims, the Bella Coola, Silver Leaf, Ladybird, Good Hope, and May P.J. Intermittent development work was carried on from 1946 until 1957 when the mine was closed. To date some 730 metres of underground work has been done in 2 long and several short adits. A total of 600 feet of surface diamond-drilling was done in 1951.
An airborne geophysical survey was carried out in the area on behalf of Atna Mines in 1969 (Assessment Report 2320).
In 1991, Westmin Resources had an airborne magnetic and electromagnetic survey conducted over the Premier Gold property totalling 760 kilometres. This survey covered an extensive area from the south end near the Premier mine area, north to the Yellowstone area.
In 2009, prospecting and chip sampling found a base-metal-bearing sulphide vein along a stream gully above the old Silver Tip underground workings (Assessment Report 31489). Chip samples yielded low gold values although elevated silver, lead and zinc were present. A chip sample over 14.0 metres yielded 4.25 grams per tonne gold and 1996.7 grams per tonne silver (Kirkham, G. (2012-06-18): Technical Report on the Resource Estimate for the Premier Gold Property). Two holes (P09-038 and 039) were drilled 30 degrees either side of north to target the thin vein (<1.0 metres true thickness) which appeared to be dipping to the south. Gold values were low as they were in surface samples although results indicated elevated silver, lead and zinc grades. One of the few significant drill results was 3.01 grams per tonne gold, >200 grams per tonne silver, 0.24 per cent lead and 0.44 per cent zinc over 0.40 metre at 75.90 metres in P09-038; 10.01 grams per tonne gold was obtain from a 1 metre interval at 44.40 metres in drill hole P09-039 (Assessment Report 31489).
See also Yellowstone (104B 039) and Premier (104B 054) for related details of the Dilworth and Premier properties that were held as a single entity in the 2000s by Bolden and Ascot Resources.