ARK, ARK VEIN, HANGINGWALL VEIN, H.M. Prospect. Tenure 555586 covers 84.233 Ha.
Extract from MINFILE No 092F 230:
The Ark occurrence area is underlain by locally pillowed to massive andesite flows and tuffs of the Upper Triassic Karmutsen Formation (Vancouver Group) exhibiting a regional propylitic alteration assemblage consisting of chlorite, pyrite, local carbonate and epidote. Alteration increases near the sheared contact with Middle to Early Jurassic Island Plutonic Suite quartz diorite. A dominant structural feature, the "Ark" shear zone, strikes 135 degrees and dips 75 degrees southwest. A hydrothermal alteration assemblage comprising argillization, chloritization, bleaching, lesser silicification, hematite, limonite and sericitization, is associated with this shear structure and overprints the regional alteration assemblage.
The "Ark" shear zone ranges to 6 metres in width and hosts the Ark vein system which consists of a 2 metre wide zone of intense alteration hosting semi-continuous quartz veins 10 to 40 centimetres in width. The alteration assemblage comprises sericitization, silicification and intense bleaching. Mineralization within this zone consists of stibnite and lesser amounts of cinnabar and realgar. The vein material has been brecciated and re-silicified. Rock samples from surface exposures assayed up to 4.08 per cent antimony, 85.9 grams per tonne mercury and 1.07 grams per tonne gold (Assessment Report 16632). Previously in 1986, grab samples from trenches assayed up to 18.3 per cent antimony, 22 grams per tonne mercury and 15.4 grams per tonne silver (Assessment Report 15147).
Drilling failed to intersect the Ark vein system at depth but encountered the Hangingwall vein system 30 metres in the hangingwall of the projected location of the Ark vein. Andesite tuffs host the Hangingwall vein system which consists of anastomosing quartz veins, stringers and brecciated and altered wallrock fragments.
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