The West Horizon area is volcanic rocks which may belong to the Upper Cretaceous Kasalka Group. This package is intruded by a quartz monzonite stock of the Eocene Nanika Intrusions.
The West Horizon zone mineralization consists of:
1) Very fine to medium-grained (1 to 3 millimetres) disseminations of pyrite, chalcopyrite and molybdenite. Total sulphide content generally ranges from 1 to 3 per cent however local concentrations of 5 per cent and more are present. Chalcopyrite often occurs proximal to biotite grains.
2) Fracture controlled chalcopyrite and molybdenite. Fracture density can exceed 10 to 20 per metre.
3) Chalcopyrite and molybdenite in quartz veinlets of numerous orientations and from 1 millimetre to 1 centimetre wide. The latter often occurs along veinlet margins. Veinlet density ranges from greater than 1 per metre to locally greater than 10 per metre.
4) Chalcopyrite and molybdenite as fracture and veinlet fillings in host tuffs and conglomerates.
Alteration of the quartz monzonite is pervasive consisting of varying intensities of clay (argillic), potassic and sericite. A pale, bleached appearance is not unusual with colours of off white, pale grey to pale green. Clay alteration is occasionally intense and wetted core will show protrusions of “swelling clays” which are likely a result of feldspar alteration. Silica is manifested by varying intensities of quartz stockwork veining and localized flooding. Potassic (K-feldspar) alteration imparts a pinkish or salmon colour to the entire core or as haloes around quartz veinlets and fractures. Secondary biotite is also present as fine grains. Locally biotite “books” are present as coarse (up to 1 centimetre) aggregates in quartz veins.
In 2011 petrographic analysis of a suite of intrusive rocks confirmed these rocks to be quartz monzonite. Two supracrustal (host) rock samples identified intermediate felsic composition ash tuffs that typically lack lithic fragments. Thus the term andesitic ash tuff is the currently used nomenclature. Four hydrothermal alteration assemblages were also identified from this work and include: potassic, sericitic, sericitic-hornfels and calcite-chlorite.
Little was known of this area prior to the company’s 2010 drilling program. Mapping by Equity Silver and the BC Geological Survey indicates a two-kilometre long, north striking quartz monzonite intrusion. In the West Horizon zone there are virtually no rock outcroppings although there is a contact shown (inferred) in the immediate area. The closest intrusive outcroppings are mapped approximately 350 metres west of Bessemer Creek however there is no documentation of any significant mineralization. In 2010 construction of a short drill access road for drill holes SH10-02/03 exposed quartz monzonite bedrock containing disseminated chalcopyrite and molybdenite mineralization. Hornfelsed andesitic rocks containing disseminated chalcopyrite were also found at this site.
In the 2010 program drill hole SH10-04 intersected extensive lengths of crackle brecciated ash tuffs deeper below the Hope Zone. Elevationally lower and to the west drill holes SH10-05 and 06 encountered a chalcopyrite-molybdenite mineralized quartz monzonite intrusion referred to as the West Horizon.
In 2011, drilling by Finlay Minerals at the West Horizon porphyry intersected long intervals of disseminated and fracture/veinlet controlled chalcopyrite and molybdenite in three holes. Hole SH11-05, a 603 metre vertical hole, cut mostly continuous mineralized porphyry. Intersections included 182 metres of 0.31 per cent copper and 0.013 per cent molybdenum followed by 364 metres of 0.11 per cent copper and 0.057 per cent molybdenum (Assessment Report 32622). Phase II consisted of eight holes totaling 3,602 metres targeting the West, Main and East Zones. Drill holes SH11-09, 10 and 13 in the West Horizon again intersected long intervals of copper-molybdenum mineralization. By 2011 eight holes delineated mineralized porphyry for approximately one kilometre from the north property boundary south to hole SH11-13. The porphyry is open to the north, south, and west and to depth. Significant copper-silver plus/minus gold mineralization also occurs well into the adjacent volcanics and sediments.
Refer to Gaul (093L 256) for further geological and work history details of the Silver Hope property.