The Homestake Ridge prospect is located 1.5 kilometres west of Homestake Creek in the Upper Kitsault Valley, 32 kilometres north of Alice Arm. The prospect has been extensively explored since 1916.
The area is underlain by a sequence of volcanics and sediments of the Upper Triassic Stuhini Group and the Lower Jurassic Hazelton Group. The sequence is folded into the doubly plunging, north-northwest trending Kitsault River syncline and has been regionally metamorphosed to greenschist facies.
The prospect is situated at the northern end of a 10 kilometre long northwest trending body of gossanous plagioclase-hornblende porphyritic andesite. This Lower Jurassic Hazelton Group unit, informally called the "Copper Belt", has been extensively pyritized and variably silicified and sericitized along its length. Mineralization and alteration is focused on subvolcanic porphyry intrusions and their felsic volcanic equivalent belonging to the Mount Dilworth Formation (Hazelton Group).
Mineralization occurs as disseminations and massive lenses, up to 1 metre wide, in veins and pockets of quartz, carbonate and barite. These occur within a zone which contains several subparallel faults. This zone strikes northwest for at least 270 metres, dips 50 to 80 degrees northeast and is 4.6 to 12 metres wide, with widths commonly around 6 metres. The southern 49 metres of this zone has been displaced 60 metres to the east by an east-northeast trending fault. Mineralization consists of pyrite, minor chalcopyrite and traces of sphalerite and galena.
A 7.98 tonne sample of sorted ore, displaying lenticular bodies of pyrite and chalcopyrite over a width of 4.6 metres, averaged 140 grams per tonne gold, 203 grams per tonne silver, 7.5 per cent copper, 0.795 per cent lead and 3.80 per cent zinc (Minister of Mines Annual Report 1951, page 14). The gold appears to be associated with chalcopyrite. Gold values from underground workings tend to be lower and quite erratic.
A second zone, possibly a branch of the main zone, lies just to the north. It strikes 095 degrees, dips 75 degrees north, has been traced for 90 metres and is 3 to 4 metres wide. The zone contains pyrite with sparse chalcopyrite, galena and sphalerite in a gangue of silicified andesite with some calcite.
The Homestake zone comprises the Homestake and Homestake Silver. The Homestake zone consists of a series of silica to silica-carbonate-chlorite altered lenses and hydrothermal breccias which have a northwesterly strike and dips moderately northeasterly at slightly greater angles than the topographic dip slope. Gold and silver mineralization occurs with pyrite, chalcopyrite and lesser galena and sphalerite in stronger areas of silica alteration or hydrothermal brecciation within zones of sericite-pyrite altered feldspar-hornblende phyric volcanics. Only along the southwestern flank of the Homestake zone does lower grade gold mineralization penetrate up into the overlying package of basinal filling volcano-sedimentary and andesitic rocks which comprise the “hangingwall” sequence. Native gold along with pyrargyrite and acanthite have been observed hosted within quartz veins and quartz-carbonate hydrothermal breccias in drill core. The Homestake gold-bearing zone as currently known is about 400 metres long and has been traced downdip by drilling for a distance of about 500 metres. At the surface, the northwestern extent of the mineralization is obscured by a glacier, while to the southeast, surficial geochemistry indicates that an anomalous zone continues on strike for at least another 700 metres towards the Homestake Silver zone. Widths at the main zone vary up to about 60 metres (approximate true width) depending on the assay cut off that one wishes to apply. The mineralization does not occur within sharp boundaries as would be the case of a well-defined vein structure, but requires assaying to delineate the grades. The zone has a complex form which may consist of a faulted complex of lenses and related steeply dipping feeders. At the current level of knowledge, the mineralization must be considered to be open in all directions. Although the mineral zone itself is fairly continuous, the enclosed values and zone thickness fluctuate indicating the presence of underlying structural variations and an inhomogeneous gold distribution.
About 800 metres further to the southeast, the Homestake Silver zone is comprised of a series of hydrothermal breccias which are galena-sphalerite and silver-rich, rather than being gold-bearing with chalcopyrite as occurs within the Homestake zone. As in the Homestake zone, these hydrothermal breccias trend northwest-southeast but dip vertical to subvertically to the north compared to the moderately dipping Homestake zone. The Homestake zone, including Homestake Silver has been tested by about 15 historical trenches, three old adits and a total of 113 drillholes.
From 1914 to 1939, discovery of a number of gold showings on the Cambria claims resulted as a spinoff from exploration on the adjacent Homestake, Vanguard and Vanguard. From 1964 to 1979, local prospector Dwight Collison put in extensive time working a number of the showings and staked the entire area. From 1979 to 1980, Newmont Canada optioned the property from Collison and put in a grid for magnetic and Max-Min geophysical surveys as well as geological mapping and rock and soil collection. From 1986 to 1988, the open ground was staked by S. Coombes and D. Nelles and was optioned to Cambria Resources Ltd. They conducted geological mapping, rock sampling, blast trenching, and induced polarization (IP) and resistivity geophysical surveys. From 1989 to 1991, Noranda optioned the property and established a grid, and collected extensive silts, soils and rock samples. They also conducted geological mapping and magnetic, IP and resistivity surveys followed up by 12 diamond-drill holes. The reduced Cambria claims held by S. Coombes were optioned by Teck Corp in 2000. Teck staked the balance of the property. An orientation geological survey was conducted to examine numerous occurrences and to determine the geological environment. In 2001, Teck mapped the property and collected 686 rock samples for analysis.
In 2003, Bravo Venture Group Inc. acquired the Homestake Ridge and focused its drill program primarily on structurally controlled gold mineralization (103P 216) in the Goldslide pluton rather than exploring for a precious metal enriched volcanogenic massive sulphide (VMS) deposit as Teck Cominco Ltd. had. Six holes tested a zone of quartz-pyrite stockwork veining and breccia at the contact of the feldspar-hornblende porphyry stock. Bravo drilled five additional holes to test four other targets: the rhyolite/argillite contact formerly explored by Teck Cominco, the Silver Crown zone (103P 082), and the Fox-Gold Reef zone (103P 093, 213), and the Dilly vein.
During the 2004 field season, Bravo focused on delineating the strike potential of the main Homestake shear. Ten line-kilometres of cut grid were established over the main and adjacent structures. Soil sampling and ground magnetic geophysics were conducted over the grid. Several zones of interest were identified mapped and sampled. Bravo Venture Group Inc. returned to the Homestake Ridge gold prospect (103P 216) to complete 1643 metres of drilling in 11 holes, intersecting significant gold-silver values. Mineralization occurs as an extensive zone of breccia and quartz veins near the contact of the Goldslide hornblende-feldspar porphyritic stock. The style of mineralization is comparable to deeper levels of the Silbak Premier deposit (104B 054). The 2005 drilling at Homestake Ridge tested a northwest structure over a 300 metre length. Hole HR05-13 intersected 4.1 metres grading 7.9 grams per tonne gold and 554.6 grams per tonne silver and hole HR05-17 cut 7.4 metres grading 10.6 grams per tonne gold and 21.8 grams per tonne silver, demonstrating the range from modest to high silver grade (Exploration and Mining in British Columbia 2005). In 2006, Bravo Ventures Group Inc. completed a 28-hole diamond drilling program (6588 metres) and four days of geological mapping on their Homestake Ridge project. In 2008, Bravo Ventures continued with a 42-hole diamond drilling program (8724 metres) and three days of geological mapping. In 2009, 684 line-kilometres of heli-borne AreoTEM electromagnetic, magnetic and radiometric geophysical surveying was conducted over the Homestake claims on behalf of Bravo Gold Corp. of Manex Resource Group.
In May 2010, Bravo Gold Corp. released resource estimates for the main Homestake zone of 0.888 million tonnes indicated grading 6.69 grams per tonne gold, 47.2 grams per tonne silver and 0.15 per cent copper; and 1.140 million tonnes inferred grading 5.02 grams per tonne gold, 50.9 grams per tonne silver and 0.25 per cent copper. For the Homestake Silver zone, inferred resources are 1.2 million tonnes grading 4.25 grams per tonne gold, 158.0 grams per tonne silver and 0.02 per cent copper (Vancouver Stockwatch News Release - May 14, 2010).
In December 2012, an updated resource for the Homestake Ridge project was reported at 0.604 million tonnes indicated grading 6.40 grams per tonne gold, 48.3 grams per tonne silver and 0.181 per cent copper with 6.77 million tonnes inferred grading 4.19 grams per tonne gold, 93.6 grams per tonne silver and 0.111 per cent copper, using a NSR cut-off value of US$85 per ton cut-off (Macdonald, R. (2013-06-07): Technical Report on the Homestake Ridge Project – An Updated Mineral Resource).
In 2013, Agnico Eagle Mines Ltd. assumed project management under an option agreement signed in August 2012, to finance exploration and development costs over a five-year period to earn a 65 per cent interest in the Homestake Ridge property. In 2014, Homestake Resource Corp. received notice from Agnico Eagle Mines Ltd. of its intention to let lapse its option to earn an initial 51 per cent interest in the Homestake Ridge property, with Homestake retaining 100 per cent ownership of the property. To date (ca. 2014), 268 holes have been drilled for a total of 77,845 metres. Homestake’s drilling resulted in an inferred resource totalling 6.8 million tonnes grading 4.2 grams per tonne gold, 93.6 grams per tonne silver and 0.11 per cent copper. The South Reef discovery (late 2011) is a high-grade zone that remains open to the northwest and lies 800 metres southwest of the Homestake Silver zone. South Reef adds 332,000 inferred tonnes grading 13 grams per tonne gold and 3.6 grams per tonne silver (Press Release – Homestake Resource Corp., May 6-12, 2013).
In 2015, the property was optioned to Banks Island Gold Corp.
In 2017, Auryn Resources Inc. carried out a 37 hole, 14,850 metre diamond drilling program. Drill result highlights include 30 metres of 2.00 grams per tonne gold (including 4 metres of 6.03 grams per tonne gold and 2 metres of 11.80 grams per tonne gold), 10 metres of 4.12 grams per tonne gold (including 2 metres of 18.01 grams per tonne gold), 18 metres of 1.29 grams per tonne gold (including 4 metres of 4.18 grams per tonne gold), 8 metres of 2.67 grams per tonne gold (including 2 metres of 7.4 grams per tonne gold), and 14 metres of 1.23 grams per tonne gold.
In 2017, Auryn Resources Inc. produced a new mineral resource at a 2.0 grams per tonne gold equivalent cut-off (Information Circular 2018-1, page 21):
Indicated: 0.624 million tonnes at 6.25 grams per tonne gold, 47.9 grams per tonne silver and 0.18 per cent copper;
Inferred: 7.245 million tonnes at 4.00 grams per tonne gold, 90.9 grams per tonne silver and 0.11 per cent copper.
In 2019, Auryn Resources Inc. reported an updated mineral resource for the Homestake Ridge Gold project of 736 000 tonnes indicated grading 7.02 grams per tonne gold, 74.8 grams per tonne silver, 0.18 per cent copper and 0.077 per cent lead of the main Homestake Ridge zone plus an additional 5 545 000 tonnes inferred grading 4.58 grams per tonne gold, 100.0 grams per tonne silver, 0.13 per cent copper and 0.142 per cent lead for the main Homestake Ridge, the Homestake Silver and the South Reef zones using a 2.0 grams per tonne gold equivalent cut-off grade (Auryn Resources Inc. [2020-06-24]: Technical Report, Updated Mineral Resource Estimate and Preliminary Economic Assessment on the Homestake Ridge Gold Project, Skeena Mining division, British Columbia).