The Coyote occurrence lies in the Coyote Creek drainage basin, approximately 1.2 kilometres west of Ealue Lake and 10.5 kilometres south-southeast of the village of Iskut.
The property is extensively covered by Quaternary surficial deposits; limited bedrock exposures suggest that the underlying geology consists of flows, tuffs, and breccia of the Lower-Middle Jurassic Hazelton Group. At the Coyote showing, this sequence has been intruded by a monzodiorite body which was itself intruded by a quartz monzonite dike, possibly related to the Early Jurassic Rose and Edon plutons (Geological Survey of Canada Open File 1080).
The Coyote showing comprises a mineralized quartz vein with minor sections of stockwork hosted by a quartz monzonite dike. The hostrock has undergone propylitic alteration with quartz-sericite alteration concentrated along the vein margins. Mineralization comprises locally abundant disseminated pyrite and pyrrhotite with rare disseminations of molybdenite and chalcopyrite. Analytical results from drill chips were not reported.
The area was initially explored in 1975 by geological and geochemical means, followed by a limited (five holes, 293 metres) percussion drilling program. The property has seen minimal exploration since that time. While acquiring an option on the Rok property in 2004, Firesteel Resources Inc. undertook a small rock and soil geochemical sampling program in the area of the Coyote showing. Forty-eight soils and 33 rock samples were taken from a small grid. In 2005, a helicopter-borne geophysical survey by Aeroquest Ltd. was carried out on behalf of Firesteel Resources Inc. on the Rok property. The survey comprised a new tri-directional magnetic gradiometer system, and a gamma ray spectrometer system. The airborne survey was flown at 200 metre line spacings with a total survey coverage of 611.4 line-kilometres. In 2009, Brett Resources Inc. initiated exploration for copper-gold-molybdenum mineralization over a coincident, airborne magnetic high anomaly outlined west of the Coyote showing by the Aeroquest Ltd. survey carried out in 2005. Grid lines cut in the fall of 2007 at approximately 200 metre spacings were resurrected and re-flagged with picket stations established at 50 metre intervals. The lines were covered by ground magnetic and induced polarization geophysical surveys and soil sampled on 50 metre spacings. A total of 23.5 line-kilometres (on eight grid lines) of induced polarization and ground magnetic surveys were completed over the Coyote grid. Additional soil sampling at 50 metre intervals was carried out along the access road to the Red Chris exploration camp and along Ealue Lake road. A total of 378 soil samples were collected from eight cut grid lines plus 1900 metres along the Red Chris exploration camp access road and 1600 metres along the Ealue Lake road.
The 2009 exploration program completed 23.5 line-kilometres of induced polarization and ground magnetics over the Coyote grid. Two strong northwest trending chargeability and coincident resistivity highs were identified within the Coyote grid, open along strike and at depth. A northwest trending magnetic high was identified in the lower half of the grid, open along strike. Soil sampling (378 samples) was done in and around the Coyote grid. Sampling identified a coincident gold-molybdenum anomaly over a portion of the northern half of the Coyote grid. Copper values are elevated in the same area, but erratic. The soil anomaly area is underlain by a strong chargeability-resistivity high coincident with a moderate magnetic response. Rock samples (135 chip and 1 grab samples) were taken along roads. Sample results range up to 1585 parts per billion gold, 2024 parts per million copper, and 812.6 parts per million molybdenum (News Release - Firesteel Resources Ltd., January 20, 2011).
In 2013, OZ Exploration Pty Ltd. (OZ) carried out an exploration program at the Rok Coyote Project, under a Joint Venture agreement with Firesteel Resources Inc. The 2013 exploration program included an Archaeological Overview Assessment, 26.5 kilometres of transmitter line 3D offset line pole-dipole induced polarization/resistivity, 316 line-kilometres of airborne magnetic and radiometric, three diamond HQ-NQ holes totalling 1740 metres and field geological mapping to ground truth historic mapping. The induced polarization survey has verified historic results in the areas of Main and West zone. Several chargeable and resistive anomalies have been highlighted some of which were tested during the 2013 drilling program. Drilling results show that chargeable conductive zones such as Main zone are related to highly pyritized (7 to 8 per cent) volcanic rocks devoid of copper sulphides (Assessment Report 35259).
In 2014, 44.85 line-kilometres of induced polarization was completed, centred on the Coyote and Klappan (104H 014) prospects. The induced polarization survey at Coyote (38.77 kilometres) delineated three chargeability highs, two which trend northwest with strike lengths greater than 1500 metres and 1200 metres, respectively. Magnetic data over the same area also exhibit strong northwest trends. Two drillholes (totalling 842.15 metres) targeting alkalic porphyry copper-gold mineralization were completed at the Coyote prospect. In drillhole DD14RK005, patchy gold mineralization was intersected in weakly hydrothermally altered crystal tuff and abundant pyrite in the upper portion of the hole, with the best 3-metre intercept assaying 0.99 gram per tonne gold from 142 metres downhole. Drillhole DD14RK006 intersected intensely chlorite-altered volcanic rocks intruded by weakly mineralized monzonite dikes in the lower part of the hole (below 383 metres) with disseminated chalcopyrite-pyrite mineralization zones producing anomalous copper and gold values; including 109.1 metres assaying 0.11 gram per tonne gold and 0.05 per cent copper (News Release - Firesteel Resources Inc., November 14, 2014).
In 2017, Colorado Resources undertook geological mapping, prospecting, soil (2208 samples) and rock (159 samples) sampling program on the central and southern portions of the North Rok property (104H 035). Geological mapping was accomplished over approximately 9 square kilometres. Compilation and interpretation of historic induced polarization and magnetic data was also completed. All these programs were conducted on portions of the North Rok claims acquired from Firesteel Resources Inc. (formerly Rok-Coyote - see March 13, 2017 press release) and not covered by exploration programs conducted by Colorado Resources between 2012 and 2014. In addition, a 6-hole (2529 metres) diamond drill program was completed, to test mineral potential downdip from 2013 and 2014 North Rok drill intersections and to test mineral potential southwest of previously outlined zones. Outcomes of these programs were highly anomalous areas of greater than 50 parts per billion gold and greater than 200 parts per million copper in soil and talus fines with strike lengths greater than 7.5 kilometres and widths up to 1500 metres. Anomalies had an association with fine-grained plagioclase-phyric monzonites and monzodiorites, associations with contacts between intrusions and Hazelton Group volcanic rocks, and a preferred association with thin, laterally persistent carbonate units. Plotting up the historic and recent soil geochemical data (greater than 9000 samples), has highlighted seven anomalous areas with greater than 200 parts per million copper plus elevated gold in soils. The greater than 200 parts per million copper in soils anomalies and the distribution of gold and copper in rock samples characterize a 9-kilometre-long favourable copper and gold mineralized trend (Assessment Report 37578).
The areas are:
• Mabon Area at North Rok (104H 035)
• Edon Area (1.5 kilometres to the southeast of Mabon) (104H 004)
• Silver Standard Area (3.0 kilometres to the southeast of Mabon)
• West Area (4.25 kilometres to the southeast of Mabon) (104H 002)
• MFJ Area (4.25 kilometres to the east-southeast of Mabon) (104H 001)
• South Area (6.5 kilometres to the east-southeast of Mabon) (104H 006)
• O.K. Area (6.5 kilometres to the east-southeast of Mabon).
Induced polarization data compilation indicates that the 20 mV/V chargeability contour outlines the Mabon stock as well as coarse fragmental rocks of the Hazelton Group. Magnetic data compilation is generally discontinuous and better tracks portions of known mineralized zones, compared to the induced polarization data. Both Hazelton and Stuhini groups supracrustal units have significantly enhanced magnetic signatures. Highly magnetic intrusive and supracrustal units convert to magnetic lows proximal to faults, suggesting that the faults are magnetite destructive.
Geological mapping extended the Mabon monzodiorite stock for approximately 2000 metres south towards the Silver Standard and West occurrences. The Mabon stock hosts an inferred resource of 142.3 million tonnes of 0.22 per cent copper and 0.26 gram per tonne gold. Prospecting and rock and soil sampling indicate that the Mabon Stock extensions are also locally gold and copper mineralized and the stock may have enhanced copper-gold mineralization along its northeastern contact, proximal to the Mabon Creek Fault. The Mabon Creek Fault places younger hematitic Hazelton Group volcanic and tuffaceous rocks against older Stuhini Group mafic volcanic rocks and small plugs and dikes of the Edon stock locally cut the fault. This suggests that the Mabon Creek Fault predates mineralization and may act as a control on copper-gold distribution (Assessment Report 37578).
Geological observations and supporting 2017 programs suggest three styles of copper-gold mineralization at North Rok. Porphyry copper-gold mineralization associated with fine-grained plagioclase phyric Upper Triassic-Jurassic intrusions (e.g. Mabon, Silver Standard, and West). Copper plus/minus gold mineralization associated with calc-silicate skarns hosted by thin, laterally persistent limestone and limy shale intravolcanic units (e.g., HI occurrence). Disseminated and fracture-controlled mineralization is preferentially developed in coarse-grained, locally hematitic mafic fragmental rocks of the Hazelton Group.
Geological mapping and subsequent 2017 drill testing refined characteristics of the Mabon zone, where mineralization is predominantly hosted in portions of an elongate 5000 by 1000 metres fine-grained, quartz-deficient plagioclase phyric monzodiorite intrusion (Mabon stock).
The Mabon stock and enclosing volcanic rocks host a well defined, strongly zoned hydrothermal and contact metamorphic alteration assemblage. Alteration zones range from high temperature potassic alteration, through quartz-pyrite (phyllic), to low temperature epidote-chlorite, copper and gold mineralization, as disseminated and vein-hosted chalcopyrite, has been defined by drilling over a strike length of 1000 metres at the Mabon zone.
The Mabon stock has been U-Pb dated at 215.8 ±3 Ma with the timing of mineralization based on Re-Os dates at 207.2 ±0.9 Ma. This suggests that the timing of mineralization is similar to Red Chris (203.8 Ma) (104H 005), and forms part of a Triassic intrusion-related mineralizing event within the Iskut area. Geochronological data indicate that the Mabon stock intrudes either the Lower Hazelton Group volcanic rocks or rocks of the Upper Triassic, near the Hazelton-Stuhini groups unconformity (Assessment Report 37578).
The 2017 diamond drill (NQ core) program demonstrated that expansion of the 2014 inferred North Rok resource will likely occur. Drillhole DDH NR 17-035 results indicate that strong copper-gold intersections may exist up to 350 vertical metres below 2013 drillhole traces: drillhole NR 17-035 - 54.0 metres of 0.61 gram per tonne gold and 0.22 per cent copper (329.4 to 383.4 metres) and 187.9 metres of 0.41 gram per tonne gold and 0.32 per cent copper (443.8 to 631.7 metres). Also, the potential exists for deeper intersections to have sufficient gold-copper values to support underground mining scenarios; drillhole NR 17-035 - 30 metres of 1.38 grams per tonne gold and 0.36 per cent copper (447.4 to 477.4 metres). The geometry of the North Rok copper-gold mineralized zones may diverge from previously proposed highly planar intrusive and structural model, as drillhole DDH NR 17-038 intersected 130.4 metres of 0.33 gram per tonne gold and 0.17 per cent copper (490.0 to 620.4 metres) in a volume of monzonite previous drilling had suggested to be non-mineralized. A second mineralized zone likely exists significantly to the southwest of the 2014 inferred resources area; drillhole DDH NR 17-037 - 18.3 metres of 0.42 gram per tonne gold and 0.10 per cent copper (2.7 to 21.0 metres). This drillhole may represent an up-dip extension of a mineralized zone cored earlier in drillhole DDH NR 14-031 (Assessment Report 37578).
