The North zone showing is situated approximately 2.3 kilometres south of Mitchell Bay on the Redgold property. The Redgold (Shik or Shiko Lake) property is situated between Quesnel Lake to the north and Antoine Lake to the south, approximately 70 kilometres northeast of the town of Williams Lake. The property is accessed by a paved road north of Highway 97, 9 kilometres east of Williams Lake. Local access for the claim block is excellent due to a good network of logging roads and trails that are accessible from the community of Horsefly. The property can also be approached from the “Ditch” Road, which runs along the west side of Quesnel Lake from Likely.
The Shiko Lake prospect occurs within the central Quesnel Belt, a belt of Triassic to Jurassic, dominantly volcanic rocks with associated alkaline stocks. The volcanics form part of the Nicola Group, which extends from near the British Columbia–United States border in the south to east of Quesnel in the north.
The regional stratigraphy has been interpreted as being folded into a broad, block-faulted syncline. An older, Upper Triassic basaltic-derived package occupies the margins of the syncline and a younger, Lower Jurassic mafic volcanic package comprises much of the core of the syncline. The oldest identified rocks in the folded sequence are of Carnian age (Upper Triassic) and are composed of basaltic siltstone, sandstone and conglomerate, minor volcanic breccias, limestone and argillite. Succeeding this package are Norian augite phyric flows, pillow lavas, breccias and volcaniclastics with local limestone lenses. Lower Jurassic assemblages feature a thick succession of heterolithic felsic breccias, debris flows and associated intrusive rock, all having alkalic composition. A belt of Lower Jurassic intrusive alkalic rocks cut the Upper Triassic and Lower Jurassic assemblage. These alkalic stocks range in composition from diorite to monzonite to syenite. Some of the literature suggests that the intrusive complexes represent various eruptive volcanic centres and are coeval with some of the later volcanics.
The Shiko Lake property is centred on a Lower Jurassic intrusive complex known as the Shiko Lake or Shiko stock and is composed of diorite grading into syenite and monzonite. This stock is surrounded by older and coeval, comagmatic sedimentary and volcanic units. The intrusive complex displays a high magnetic signature and the sedimentary and volcanic stratigraphy represents local areas of high chargeability due to increased sulphide content.
Outcrop is generally scarce in the property area due to locally thick accumulations of glacial till and glaciofluvial deposits. Bedrock is exposed mainly on ridge lines and where otherwise shallow overburden has been disrupted by industrial activity, such as logging and road building. Within the property claim boundary, the Shiko Lake stock has intruded the Nicola Group volcanic and sedimentary rocks. On the property, the Nicola Group has been subdivided as follows:
• Triassic augite basalt—interlayered augite-bearing basaltic flows, tuffs and wackes;
• Jurassic felsic breccia—heterolithic breccias (volcanic or intrusive?) associated with the intrusive complex;
• Jurassic siltstone—massive to locally laminated tuffaceous sediment;
• Cretaceous Shiko stock intrusive complex—syenite, monzonite, diorite, gabbro;
• Jurassic maroon basalt—analcite-bearing, subaerial? basalt flows and breccias; and
• mafic and felsic dikes.
Hydrothermal activity associated with the intrusion of the stock has produced pods and lenses of epidote-chlorite-calcite alteration within basaltic rocks and alteration of wallrock adjacent to fractures within the stock. This propylitic alteration assemblage is locally accompanied by chalcopyrite-pyrite-bornite mineralization. Some work (Exploration in British Columbia, 1987, page C245) suggests that gold and chalcopyrite were remobilized and subsequently deposited along fractures within pyrite. Assays from drillcore in 1974 ranged from 0.01 to 0.1 per cent copper and typically around 0.034 gram per tonne gold. The copper values were low and sporadic with very low gold values (Assessment Report 5540). In 1984, Falconbridge Copper Corporation completed sampling on the property with rock-chip samples returning up to 0.2 per cent (2000 parts per million) copper and 1.35 grams per tonne (1350 parts per billion gold; Property File Rimfire, Durfeld, R.M., 1984). Several areas of mineralization have been confirmed within the property.
The North zone covers the northeast extension of the main Shiko Lake diorite and its contact with highly sulphidized felsic breccia volcaniclastic hostrocks. This zone was one of the earliest exploration targets in the 1970s. Historic percussion holes and scattered Phelps Dodge diamond drill holes intercepted widespread potassic alteration (K-spar-biotite-amphibole-magnetite) with anomalous copper-gold values. Higher values of gold and copper occur locally as well (hole SLP-1 intersected 10.4 metres of 0.72 gram per tonne gold and 0.47 per cent copper; Assessment Report 5540, page 1). In 2007, drilling by NovaGold successfully duplicated the highly anomalous metal values seen in early percussion hole P-1, yielding three significant intercepts from drillhole DDH SH07-03: 8.1 metres grading 0.74 per cent copper and 2.3 grams per tonne gold (3.9 to 12 metres); 28.5 metres grading 0.39 per cent copper and 1 gram per tonne gold (29 to 57.5 metres); and 8 metres grading 0.09 per cent copper and 1.7 grams per tonne gold (89 to 97 metres; Assessment Report 29999).
The Northeast zone consists of a mineralized syenite and syenite breccia outcrop. In the area, anomalous soils and float (confirmed by 2006 resampling) were tested by Phelps Dodge drillholes SH90-5, SH90-8, SH91-9 and SH91-10, collared on the south side of the main soil grid between the North and East zones. Pervasive epidote-calcite alteration is overprinted by intense magnetite-epidote-K-feldspar alteration in holes 90-5 and 90-8; all four holes contain broad intercepts of geochemically anomalous metal. Hole SH90-5 contains 12 metres averaging 0.36 gram per tonne gold and 0.22 per cent copper (Assessment Report 20930, Appendix I, pages 3 to 4). The two drillholes completed in 1991 encountered felsic breccia, fine-grained siltstone and augite basalt. Both holes displayed weak propylitic alteration with 1 to 5 per cent disseminated pyrite and trace chalcopyrite and epidote throughout.
Anomalous to highly anomalous soil samples occur along the northwest contact of the Shiko Lake stock in an area tested by percussion hole SLP-5 (diorite) and DDH SH90-4 (felsic breccia). Summary logs for these holes indicate strong pyrite with long intervals of 0.05 to 0.1 per cent (500 to 1000 parts per million) copper averaging approximately 0.07 per cent [700 parts per million] copper on both sides of the contact (Assessment Report 5540, page 7; Assessment Report 20930, Appendix I, pages 1 to 2).
Propylitic alteration is widespread on the property but is particularly well developed in the augite basalt, felsic breccia and siltstone units occurring within tens to hundreds of metres of the Shiko Lake stock and satellite bodies. In detail, the character of the propylitic assemblage varies with location and with rock type: chlorite-pyrite-magnetite-calcite-ankerite (felsic breccia), chlorite-pyrite (siltstone) and chlorite-epidote-calcite-pyrite-chalcopyrite (augite basalt).
In 1964, the Mount Polley (MINFILE 093A 008) copper-gold porphyry deposit was discovered as the result of an investigation on a prominent aeromagnetic anomaly. The Mount Polley discovery encouraged exploration for additional copper-gold porphyry deposits within the area. As a result, in 1969 the Shiko Lake property was targeted based on a regional airborne magnetic survey flown by the Geological Survey of Canada.
Since 1969, the intrusive complex and the surrounding property have been held by various owners and operators. Between 1969 and 1974, Kerr Addison Mines and Cariboo Syndicate performed induced polarization and geochemical work. Terramar Resources completed 320 metres of diamond drilling over three holes from 1980 to 1982. J.W. Morton and R.M. Durfeld staked the Shiko claims after Terramar allowed them to lapse in 1982. Between 1982 and 1989, Morton and Durfeld performed mapping, induced polarization and very low-frequency geophysical surveys and geochemical work. From 1989 to 1992, Phelps Dodge Corporation completed a 66-square-kilometre soil sample grid, 37 line kilometres of induced polarization surveying and 1997 metres of diamond drilling.
The area was first staked by Kerr Addison Mines and Dusty Mac Mines in 1969, when Kerr Addison completed 7 kilometres of magnetometer geophysical surveying, geological mapping and an 80-sample geochemical survey. The following year, Dusty Mac Mines completed 26 kilometres of induced polarization geophysical surveying, 500 metres of bulldozer trenching and geochemical sampling on the 291 claim group, which included the future Redgold, SL and Shiko claim areas. Dusty Mac Mines allowed the claims to lapse in 1971. In 1972, Fox Geological Consultants Limited staked the SL claim group over the area on behalf of the Cariboo Syndicate—a joint venture funded by Dome Mines Limited and Newconex Canadian Exploration Limited. Between 1973 and 1974, exploration consisted of 16 kilometres of induced polarization and magnetometer geophysical surveying, soil and rock sampling, geological mapping and 280 metres of percussion drilling in seven drillholes. Three of the drillholes were completed in the area of the North zone. No work was completed after 1974 and 68 of the 96 claims were allowed to lapse. The remaining 28 SL claims were acquired by Terramar Resource Corporation in 1980.
In 1980, Terramar Resource Corporation completed three BQWL diamond drill holes totalling 320 metres. The drillholes targeted the syenite core of a large intrusive stock in what is now known as the Quarry zone. The property lay dormant until 1984, when Terramar Resource Corporation completed geological mapping and a 16.5-kilometre, 135-sample geochemical soil survey on the SL claims.
In 1982, the ground to the east of the SL claim group was staked by James W. Morton and Rudolf M. Durfeld as the Shik and Redgold claims. The following year, Durfeld and Morton grouped the Shik and Redgold claims into the Redgold claim group. Between 1983 and 1989, exploration on the Redgold group consisted of rock-chip geochemical surveying, ground magnetometer, induced polarization and electromagnetic geophysical surveying, soil sampling, geological mapping and bulldozer trenching. Sedona Resources Corporation optioned the Redgold property in 1986 and completed bulldozer trenching, geochemical sampling (35 samples) and induced polarization geophysical surveying over the area of the Redgold zone; however, the option was dropped shortly after.
In 1989, Terramar Resource Corporation allowed 27 of the 28 SL claims to lapse. The area was restaked by Morton and Durfeld and was consolidated with the Redgold claim group. Shortly afterward, the property was optioned to Phelps Dodge Corporation of Canada Limited. A short exploration program of line cutting, grid establishment and soil (222 samples) and rock (29 samples) sampling was completed that fall. The final SL claim expired later that year and was restaked by Phelps Dodge.
In 1990, Phelps Dodge completed 50 kilometres of grid preparation, geological mapping, geochemical soil sampling and geophysical surveying. Later that year, five diamond drill holes totalling 536 metres were completed to follow up three large and several smaller anomalies identified by geophysical and geochemical surveying. Two of the drillholes—SH90-6 and SH90-7—targeted the area of the North zone, and another two—90-5 and 90-8—targeted the area of the Northeast zone. Drilling continued in 1991 with 12 NQ diamond drill holes totalling 1458 metres. Two of the 1991 drillholes—SH91-9 and SH91-10—were drilled in the Northeast zone.
The Quarry zone, a mineralized monzonite outcrop situated to the southwest, was unexpectedly discovered by Quarry Pacific Industries Limited during quarrying operations in 1993. Earlier that year, Quarry Pacific had leased a small portion of the Redgold property from Morton and Durfeld and had begun mining part of the syenite intrusion for industrial use, including dimension stone for the Vancouver Public Library. The quarrying operation exposed a copper-gold– mineralized zone consisting of malachite- and azurite-stained fracture faces with disseminated bornite and chalcopyrite.
In spring 1996, Imperial Metals Corporation carried out an airborne geophysical survey over the Redgold and Shiko Lake properties. Later that year, Imperial Metals conducted a three-phase exploration program to determine the extent of the quarry mineralization on the Redgold property. The program consisted of extensive channel sampling, trenching, drilling and induced polarization geophysical surveying. A rock saw was used to cut 5.08-centimetre (2-inch) channels across the outcrop in a grid pattern; thirteen trenches were excavated as channel extensions and then chip sampled and assayed in 1 to 3-metre intervals. Four diamond drill holes totalling 411.6 metres were drilled to follow up significant gold and copper values obtained from the channel and trench samples.
After the option with Imperial Metals was allowed to lapse, Morton and Durfeld (through Redgold Resources Limited) conducted a limited exploration program in 1998. That year, Morton and Durfeld compiled all existing data for the property and carried out a limited prospecting and rock sampling (14 samples) program. The following year, a ground magnetic survey was completed over an area including the Redgold and Quarry zones. Rock from the Quarry zone was crushed and screened, producing an apricot-coloured aggregrate. Morton and Durfeld intended to assess the potential demand for the product as a decorative aggregrate or landscaping material.
In 2001, Durfeld and Morton carried out a program of prospecting and rock (55 samples) and soil (75 samples) sampling on the Redgold property. The following year, prospecting focused on areas south of the Redgold showing and east of the Quarry zone in an effort to locate new, unidentified outcrops. The operation was of very limited success. In the summer of 2004, a program of excavator trenching and sampling targeted newly exposed bedrock in the East and Redgold zones. Ten soil samples and 38 rock samples were collected and sent for analysis.
Later in 2006, the property was optioned to NovaGold Resources Incorporated, who collected 883 soil samples and 205 rock and chip samples over a four-square-kilometre sampling grid and 30 kilometres of road. In 2007, NovaGold completed an exploration program consisting of 11 diamond drill holes totalling 2293 metres and 12 line kilometres of ground-based, deep-sensing induced polarization–resistivity geophysical surveying.
In 2011, Gold Fields Horsefly Exploration Corporation signed an option and joint venture agreement with RedGold Resources Limited. That year, exploration focused on following up existing targets defined by previous exploration programs, in particular the 2007 NovaGold program. Exploration that year consisted of geological mapping and prospecting, grid-based regional soil sampling, ground-based magnetometer surveying, diamond drilling and compiling and interpreting historic drill records. Results of the program included improved magnetic and geological definition of the Redgold target area and expansion of the East mineralized zone.
Significant results for the North zone include drillhole SH90-6 returning 8 metres of 0.32 gram per tonne gold and 0.15 per cent copper; drillhole SH07-03 returning 8.1 metres of 2.07 grams per tonne gold and 0.64 per cent copper, 28.5 metres of 0.99 gram per tonne gold and 0.36 per cent copper and 9.9 metres of 1.54 grams per tonne gold and 0.61 per cent copper; and drillhole SH07-09 returning 12 metres of 0.47 gram per tonne gold and 0.08 per cent copper (Assessment Report 32975, page 14).
Significant results for the Northeast zone include drillhole SH90-5 returning 13.7 metres of 0.32 gram per tonne gold and 0.21 per cent copper and drillhole SH90-08 returning 18 metres of 0.32 gram per tonne gold and 0.09 per cent copper (Assessment Report 32975, page 16).