The Blackhawk occurrence is centred on an old adit located approximately 5 kilometres southwest of the settlement of Manson Creek and is accessed by a cat trail beginning at an old road on the southeast side of the Manson River. In 1981, Golden Rule Resources Limited held the Flume and OPEC (Blackhawk occurrence) claims adjacent to the Fairview occurrence.
This occurrence is hosted in the Middle to Upper Triassic Slate Creek Formation (Takla Group). The hostrocks are silicified phyllites, meta-siltstones and meta-greywackes. The rocks surrounding the veins are predominantly purple to dark-green, silicified and fine-grained metasiltstones. Where observed, bedding is contorted or masked by small quartz veinlets. Pervasive silicification obliterates most of the sedimentary structures. These rocks are approximately 2.5 kilometres north of the Cretaceous Germansen Batholith and are near the outer edge of the intrusion's metamorphic aureole. Three kilometres to the northeast lies the right-lateral, northwest-striking, probably Late Cretaceous to Paleogene Manson fault zone.
This occurrence is composed of a minimum of nine veins ranging in width between 0.5 and 3 metres. The veins are roughly subparallel and strike north-northeast (approximately perpendicular to the batholith contact) and dip steeply to the southwest. These milky, translucent quartz veins occur within a 200-metre wide quartz ‘stockwork’ zone. The sulphides occur as both massive and disseminated and include argentiferous galena, sphalerite, pyrrhotite, pyrite and minor amounts of chalcopyrite. Where massive, the most prevalent sulphide is pyrrhotite with some sphalerite.
The main zone of interest is 30 metres wide and surrounds the main vein and the adit vein. The adit is 5.48 metres in length on a bearing of 203 degrees. It follows a well-mineralized quartz vein, 0.48 metre in width, that dips steeply to the northeast. Mineralization in this zone consists of blebs of galena and pyrrhotite, which can be up to 25 centimetres in width. A mineralized 1.6-metre zone yielded 1398.8 grams per tonne silver, 3.0 per cent lead, 3.0 per cent zinc and trace gold (Minister of Mines Annual Report 1938, pages C10-11).
WORK HISTORY
The showings have been known for many years but details of the early history are lacking. The Report of Progress of the Geological Survey for the year 1897-98 mentions the sampling of a number of lead-silver occurrences in this vicinity, and the Black Hawk showings may have been known at that time. Initial exploration work on the property was done in opencuts and a 6-metre long adit. The ground was restaked in 1929 by W.F. Paquette as the Black Hawk group of four claims. Mr. Paquette and associates organized The Germansen Development Syndicate, Limited, in March 1931 to develop the Black Hawk and other nearby properties. Some open cutting was done on the Black Hawk group before the claims lapsed. The company charter was surrendered in 1935. In the early 1940s the property was reportedly owned by a Mr. J. Vlasak.
In 1980, Golden Rule Resources Ltd explored its Opec 1-10 claim group. Geological mapping, geochemical sampling, ground magnetic surveying, and ground very low frequency electromagnetic surveying were carried out over a grid area and 1022 soil samples and 35 rock samples were collected. The grid area was in the Discovery Bar area (093N 063). One rock sample was reported to have been collected from the Blackhawk, which encompassed by Opec 6 claim.
In 1989, Noranda Exploration Company conducted a program of soil sampling, mapping and diamond drilling on their Blackhawk property (Assessment Report 19501). Soil geochemistry identified an anomalous zone centred on the showing and a number of lesser anomalies throughout the grid. The sparse occurrence of outcrop found on the property limited the amount of information obtained by geologic mapping. Two diamond drill holes were completed to test the main showing. The results from the drilling proved disappointing, the veins appear to pinch out below the surface, and along strike, geochemical results from the core yielded very low values.
In 2006, Skygold Ventures Ltd conducted heavy mineral sampling throughout their large Manson Creek (MC) property. Two samples were collected from the north-flowing drainage east of the Blackhawk prospect. The sample at its mouth yielded strongly anomalous gold (Assessment Report 29274).
In 2007, Skygold conducted soil sampling over a large area of grid lines that extended south from Manson Creek covering Skelton and Lost creeks and further south over the upper reaches of a tributary of Boulder Creek (just west of the Blackjack Mountain occurrence (093N 148). The grid extended to the east over an unnamed north-flowing tributary creek of Manson River, just east of the Black Hawk prospect (Assessment Report 29898).
In 2008, work completed by Skygold included an eight-hole diamond drilling program in the Kathy prospect area (MINFILE 093N 030), regional reconnaissance rock sampling (160 samples), geological mapping and a geophysical airborne magnetic survey, which consisted of a large helicopter-borne magnetic gradiometer and very low frequency electromagnetic survey over much of their Manson Creek property. The survey, totalling 1580 line-kilometres, was flown in September, 2008 and covered the following MINFILE occurrences: Blackhawk (093N 022), Asp (093N 027), Berthold (093N 028), Kathy (093N 030), Kildare Gulch (093N 057), Lost Creek (093N 060), Manson River (093N 061), Boulder Creek (093N 088), AJM (093N 136), Bold 1 (093N 137), Blackjack Mountain (093N 148) and Bold 2 (093N 197). Of these, Kildare Gulch, Manson River and Boulder Creek are placer deposits. See Assessment Report 30701 for a full report on the aeromagnetic survey.
In 2017, Angel Jade Mines Ltd. carried out a field program with the intention of locating hard-rock sources of placer gold, and to determine if gold and base metal anomalies within the listwanite exposures could be used as a vector to high-grade mineralization. The field program focused on three regions within the Manson Creek area, the Big Bend area near the southern extent of the claim group, the Gary’s Pit area within the eastern extent of the claim group and the Blackjack Creek area within the northern extent of the claim group. Between the three regions, a total of 62 rock samples were collected and assayed. The assays returned no values of economic interest and it was suggested that future exploration would benefit from structural mapping in locating the quartz-vein–hosted coarse gold.
Refer to Kathy (093N 030) for details of the Manson Creek project, of which the Black Hawk prospect was part of in the late 2000s.
