The Big Sioux occurrence is located at an elevation of approximately 1120 metres on a south-facing slope, southwest of Tule Lake and approximately 2.6 kilometres northeast of Aspen Grove.

The deposit is located at the north end of an area of hilly upland situated in the centre of the Aspen Grove copper camp, known as the Fairweather Hills. The Fairweather Hills region is underlain by the Central volcanic facies of the Upper Triassic Nicola Group, comprising intermediate, feldspar and feldspar augite porphyritic pyroclastics and flows, and associated alkaline intrusions. The intrusions vary in composition from diorite to monzonite and are thought to be comagmatic with the Nicola Group, ranging in age from Upper Triassic to Lower Jurassic.

Locally, the area is underlain by red and green laharic breccias, augite andesite porphyry and minor sediments of the Nicola Group (Central Belt, Bulletin 69). The units generally strike north-northwest and dip east. This sequence is broken up into a series of tilted fault blocks trending north.

The occurrence is hosted in variably amphibole, augite and feldspar porphyritic basaltic andesite, subjected to extensive fracturing, shearing and faulting. Alteration minerals include abundant epidote, and minor silica and chlorite. Some microdiorite and diorite are also present.

Copper mineralization is exposed along a 300-metre long roadcut and in various old workings north of the roadcut, in an area approximately 500 metres long and 300 metres wide. Mineralization consists primarily of pyrite and chalcopyrite, as disseminations, blebs, fracture fillings, and in calcite and epidote veins. Pyrite also forms thin bands, composing up to 25 per cent of the hostrock. Malachite occurs along fractures in many surface exposures. Chalcocite forms fracture fillings in one prominent 1.8-metre-wide shear zone, striking 075 degrees and dipping 75 degrees north. Minor bornite is also reported.

In 1901, a composite grab sample from the dump of a shaft, excavated in the chalcocite-bearing shear zone, assayed 12.6 per cent copper, 0.7 gram per tonne gold and 82 grams per tonne silver (Minister of Mines Annual Report 1901, page 1181).

In 1956, drillholes 7, 8 and 9 on the occurrence area is reported to have yielded a number of copper intersections ranging from 0.20 to 0.48 per cent copper in mixed volcanics and dioritic intrusives (Assessment Report 22720).

In 1966, a grab sample from a shaft is reported to have yielded 1.82 per cent copper, whereas samples from a pit to the west of the shaft yielded from 0.41 to 0.67 per cent copper over 4.5 metres (Property File – 8531 and 8532).

In 1972, percussion drilling on the occurrence area is reported to have yielded copper intersections of 0.16 to 0.26 per cent range in holes 71-1, -2 and -22 (Assessment Report 22720).

In 1978, channel sampling of trench no. 4 assayed 0.223 per cent copper, 0.106 gram per tonne gold and 1.26 grams per tonne silver over 27 metres (Assessment Report 7100, page 11).

In 1990, a chip sample taken along the highway roadcut (HW zone) from the 150 to 160 metre mark assayed 3.27 per cent copper, 14.45 grams per tonne gold and 34.1 grams per tonne silver over 10 metres, whereas two grab samples from 150 metre mark of a brecciated and sulphide-rich zone yielded 4.12 and 5.82 per cent copper with 9.88 and 42.16 grams per tonne gold, respectively (Assessment Report 20834, page 5).

In 1991, a chip sample (91367) of mineralized andesitic tuff from the Big Sioux trenches assayed 0.773 per cent copper and 0.600 gram per tonne gold over 5.0 metres, whereas a grab sample and a 0.1-metre chip sample (91413 and 114202) from trenches located near the Giant shaft to the southwest of the Big Sioux trenches yielded 0.948 and 3.62 per cent copper with 0.800 and 1.450 grams per tonne gold, respectively (Assessment Report 21824). Also at this time, a grab sample (91414) from the Bald Hill trenches to the northwest of the shaft yielded 0.391 per cent copper and 0.09 gram per tonne gold (Assessment Report 21824).

In 1992, drilling of a coincident magnetic and chargeability high and copper-gold soil anomaly intercepted a sequence of porphyritic volcanic flows and tuff hosting quartz-carbonate-magnetite vein stockworks with chalcopyrite mineralization associated with a monzonite dike yielding up to 0.12 per cent copper and 0.15 gram per tonne gold over the total 119 metres of hole 92-6 (Assessment Report 22720).

In 1997, drilling yielded intercepts including 0.20 gram per tonne gold and 0.18 per cent copper over 20 metres of potassic-altered monzonite dike in hole BK97-05, located approximately 150 metres northwest of the previous 1992 drill hole 92-6, whereas drilling near the Big Sioux workings yielded up to 0.09 gram per tonne gold and 0.16 per cent copper in hole BK97-10 (Assessment Report 25611). Also at this time, surface sampling of the occurrence area yielded 0.750 and 0.407 per cent copper with 0.610 and 0.355 gram per tonne gold over 1 and 3 metres, respectively, from the area of drillhole BK97-05 and 92-6 (Samples 95609 and 95629); 0.813 per cent copper, 5.2 grams per tonne silver and 0.095 gram per tonne gold from a grab sample (95627) on the Bald Hill trenches; 1.25 per cent copper and 2.04 grams per tonne gold from a grab sample (95582) from an adit dump located near the south side of the highway and 0.940 per cent copper with 0.990 gram per tonne gold over 1 metre (sample 95616) from the main workings area (Assessment Report 25611).

In 2012, a drillhole (BK-12-05), situated on an induced polarization anomaly and located several hundred metres north of the main Big Sioux workings, intercepted a clay-quartz-hematite–altered shear/fault zone hosting bornite and chalcopyrite mineralization yielding 0.22 per cent coper and 0.41 gram per tonne gold over 21 metres (174 to 195 metres down hole; Assessment Report 33851).

Work History

This deposit was one of the first occurrences in the Aspen Grove copper camp to be explored. It was staked in 1899 and investigated periodically by H.H. Schmidt until 1914. One shaft, 10 metres deep, an adit, 46 metres long, and numerous pits and trenches were excavated on the occurrence area during this time. Other trenches, referred to as the Bald Hill trenches, are located on a small hill to the northwest of the (Giant) shaft and west of the main (Big Sioux) trenched area. In 1918, 44 tonnes of ore were shipped grading 9.78 per cent copper and 67.9 grams per tonne silver.

During 1956 through 1965, Noranda and associated companies completed intermittent programs of trenching, geochemical sampling, geophysical surveys and nine diamond drill holes, totalling 1193, metres on the Big Sioux and Big Kidd (MINFILE 092HNE074) occurrences.

In 1966, Dawood Mines Ltd. completed a program of prospecting, geological mapping and rock sampling on the area as the Bill claims. In 1968, David Minerals Ltd. examined the occurrence area as the Touch 2 and Halo 1 claims. Later that year, Norranco Mining and Refining Co. Ltd. completed 20.0 line-kilometres of combined ground magnetic, induced polarization and self-potential surveys on the Broatch, Halo and Ram claims.

In 1971, Frontier Explorations Ltd. and David Minerals Ltd. completed a program of soil sampling and a 32.0 line-kilometre ground magnetic survey on the area as the Halo, Ram, Lou, Chalco, Magnus and Touch claims of the Hans Haveroen Copper property. In 1972, Amax conducted program of geological mapping, geochemical sampling, ground geophysical surveys and 23 percussion drill holes on the area. During 1975 through 1980, David Minerals Ltd. conducted programs of geological mapping, self-potential surveys, trenching and five diamond drill holes, totalling 169 metres, on the area as the Halo, Touch, Broatch and Ex claims.

The area was restaked in 1989 as the Shear claims after copper mineralization was exposed in a roadcut along the north side of the recently completed Coquihalla Highway (Phase 3 - Okanagan Connector). The occurrence area was subsequently mapped, trenched, and sampled by Amex Exploration Services Ltd. in 1990, Northair Mines Ltd. in 1991 and Placer Dome Inc. in 1992. Two diamond drill holes (92-5 and 92-6) were also completed on the occurrence in 1992. In 1993, Northair Mines Ltd. completed a further program of rock sampling on the property. In 1997, Christopher James Gold Corp. completed a program of geological mapping, geochemical (rock and soil) sampling, 10 diamond drill holes, totalling 2078.8 metres, and a 13.8 line-kilometre induced polarization survey on the area as the Big Kidd property.

In 2008, Christopher James Gold Corp. completed a 1113.5 line-kilometre airborne magnetic-radiometric survey on the area.

In 2011 and 2012, Xstrata Copper Canada Corp.completed programs of prospecting, geochemical (rock and soil) sampling, six diamond drill holes, totalling 1808.7 metres, and a 56.8 line-kilometre induced polarization survey on the Big Kidd property on behalf of Jiulian Resources Ltd.