That HC zone is underlain by Upper Triassic volcanic rock of the Upper Triassic Stuhini Group.
The HC target is located approximately 360 metres east of the southern part of the Spectrum Central zone (104G 036). Bedrock exposure is poor as the showing occurs in the middle of a scree slope, however it is reported that overburden is thin and is easily scraped away from near-surface outcrops. There are no records of mineralization on historical maps, and no trenches were established in the immediate area prior to 2015.
Prospecting in 2015 uncovered several quartz-arsenopyrite veins in the area, but prospectors were unable to determine the orientation of these structures due to highly weathered, degraded rock at surface. Two grab samples taken from strongly mineralized vein material assayed 17.4 grams per tonne gold and 52.5 grams per tonne gold with greater than 1 per cent arsenic; eleven other grab and chip samples assayed 0.3 to 1.1 grams per tonne gold (Giroux, and Stacey, 2016). Twenty-eight rock samples were collected in the HC area in 1915. A strong gold-arsenic-antimony (plus/minus zinc) soil anomaly extends downhill from the area of mineralization and includes a large outcrop south of the HC showing. The soil anomaly mimics the outline of outcrop and talus apron.
In 2016, the 52.5 grams per tonne gold grab sample was followed up by chip sampling over a 7.5 metre width (Assessment Report 36675). Mineralization is hosted in quartz-sericite altered volcaniclastics with 3 to 5 per cent disseminated pyrite-pyrrhotite. The original high-grade gold sample is associated with 3 to 7 per cent coarse-grained pyrite and chlorite-sericite alteration, however, chip sampling failed to duplicate the original results, returning only 0.251 gram per tonne gold. A 50-centimetre chip sample of similar coarse pyrite and chlorite alteration 2.5 metres into the footwall returned 3.75 grams per tonne gold (Assessment Report 36675). The mineralized interval has a north-south orientation dipping at 60 degrees to the west.
Drillhole S91-80 is located 60 metres south of the HC showing and tests the strike extent of the HC showing as well as testing downdip of gold enriched grab samples from the large outcrop south of the HC showing. Drilling intersected consistently elevated gold grading 0.283 gram per tonne over the top 60.4 metres width. One 1.5 metre sample grading 2.42 grams per tonne gold was intersected that is directly below high-grade grab samples of centimetre scale quartz-carbonate-pyrite-arsenopyrite veinlets on surface. 2016 samples from this large outcrop representing 3 to 5 metre composites of quartz-sericite altered crystal tuffs with 1 to 3 per cent pyrite and gougy shear zones which yield 0.332 to 0.655 gram per tonne gold like that reported from in the drillhole (Assessment Report 36675).
Rock grabs in 2015 confirmed gold mineralization, but 2016 channel sampling did not duplicate results (Godden et al., 2017 Technical Report). The 2017 technical report by Godden et al. indicated that the 500 Colour, HC, Porphyry, 33 and Skarn zones, though separately identified in historical records, were now considered to be part of the Spectrum Central Zone.
Refer to Spectrum (104G 036) for further geological and work history details.
