Galaxy copper-gold deposit, Kamloops, Kamloops Mining Division, British Columbia, Canadai

Regional Level Types
Galaxy copper-gold deposit	Deposit
Kamloops	- not defined -
Kamloops Mining Division	Division
British Columbia	Province
Canada	Country

The Galaxy copper-gold deposit is located within the city limits of Kamloops, about 8 kilometres west-southwest of the city centre, in the Kamloops Mining Division.
There is an extended description of the property on the British Columbia “Minfile” site, current to 2020, to which interested readers are referred. This description includes much data regarding the rocks of the general area; a relevant portion pertaining to the geology of the immediate Galaxy area is quoted below:
“Locally, the Galaxy zone occurrence is a small, alkaline-type porphyry copper-gold deposit. The occurrence is hosted within a fault-bounded pendant composed mainly of dioritic phases of the Iron Mask Batholith and volcanic and sedimentary rocks of the Nicola Group. On the western margin of the property, a northwest-trending band of picrites occurs on the eastern side of a major, steeply-dipping and northwest-trending fault; on the western side of this fault, the Cherry Creek phase occurs. East of the picrite, Nicola volcanics, Sugarloaf and Hybrid phases occur above a highly foliated, hematitic red mylonite with a thickness on the order of metres. Mineralization mostly occurs within the Sugarloaf phase and Nicola volcanics in the hanging wall of this mylonitic thrust zone, believed to be part of the Cherry Creek thrust.”
Mortensen et al. (1995) described in some detail efforts to date the various phases of the Iron Mask Batholith by the U-Pb method on zircon. Although they did not report any dates for rocks in the immediate area of the Galaxy Property, they reported dates for material from the Hybrid Unit at the Ajax West pit about 4 kilometres to the south, where a weighted average of three analyses yielded a value of 204.6 ± 2.6 Ma, which they considered to be the best estimate of the crystallization of the unit. Samples from the Cherry Creek Unit at the Crescent Pit (about 3 kilometres to the north-west) yielded a weighted average value, from two analyses of this rock, of 204.5 ± 14.3 Ma. One of these dates (204.5 ± 0.6 Ma) was regarded as the best estimate for crystallization of this unit. Finally, from the Cherry Creek Unit at Ajax West, the dates are ambiguous, with values of 1154 ± 5 Ma and 198 ± 10 Ma, suggesting older inherited zircons with possibly some igneous zircon of about 200 Ma. Mortensen et al. (1995) concluded that “The U-Pb age data for the various samples in the Ajax-Afton area indicate that, with the possible exception of the Sugarloaf unit, the entire Iron Mask batholith is of earliest Jurassic age.”
Naas (2013) compiled a list of six historical resource estimates, cautioning that none of these could be considered National Instrument 43-101 compliant. The dates of the estimates range from 1969 to 1996, and demonstrate that the deposit is small and of relatively modest grade. The most optimistic gave numbers in the general range of 2 million to 4 million tonnes grading about 0.6% copper with unknown gold grades. A more recent estimate, in 1990, gave a result of 3.5 million tonnes grading 0.65% copper and 0.34 g/t gold. The most recent, and decidedly less optimistic, was 1.7 million tonnes grading 0.39% copper and 0.22 g/t gold. Clearly the only way this deposit could be mined would be as a satellite pit to a much larger operation, for example the Ajax deposit to the south. This latter project has been stalled by a combination of environmental, indigenous peoples, and general public opposition to mining in the immediate area of Kamloops. A final nail in the coffin is the fact that the putative pit would lie a mere 1,750 metres south-west of suburban Kamloops homes.
The Galaxy copper-gold deposit is included in the USGS compilation by Singer et al. (2008). The information given by Singer et al. (2008) is incomplete.
Giles Peatfield comments on the minerals reported:
The mineralogy of the Galaxy deposit is simple, with a relatively small number of mineral species to report. Comments are as follows:
Bornite: Although to be expected, bornite was noted only by Belik (1990) in logging of percussion drill chips.
Chalcopyrite: This is principal copper mineral of economic importance, reported by all workers.
Chlorite group: Belik (1990) in logging of percussion drill chips, noted chlorite as an alteration product but gave no specific mineral data.
Epidote: Most workers noted traces of epidote, generally as a late stage alteration product.
Feldspar group: Preto (1968) noted albite. Naas (2013) reported both albite and orthoclase, as did Caron (2006, 2007).
Hematite: This is common, reported by several workers. Preto (1968) described “. . . a zone of highly foliated red hematitic mylonite several feet thick . . . .”
Limonite: Although limonite is probably common, it was noted specifically by Carr (1957).
Magnetite: This is common, reported by Carr (1957), Belik (1990) in percussion drill cuttings, and by Caron (2007).
Malachite: This is fairly common, reported by Belik (1990) and by Caron (2006, 2007).
Mica group: The only reference to a mica mineral was by Belik (1990) who described sericite alteration of generally siliceous rocks.
Molybdenite: This is not common here, and indeed has been reported only by Naas (2013) who wrote that “Molybdenite was observed in drill core from GX12-04.”
Pyrite: This is relatively common here, reported by most workers.
Pyrrhotite: Minor amounts of pyrrhotite have been reported by most workers.
Quartz: This has been reported by several workers, both as silicification and as discrete veins.
Giles Peatfield comments on the rock types reported:
The rock types listed are taken from several reports. I have chosen to comment individually on the various units.
Andesite: This is a major component of the Triassic Nicola Group volcanic package.
Diorite: This was reported by Carr (1957), by Belik (1990) in percussion drill logging, and by Naas (2013).
Microdiorite: This was reported by Preto (1968).
Monzodiorite: This was reported by Caron (2006, 2007) and by Naas (2013).
Mylonite: This was reported by several workers, most notably Preto (1968).
Picrite: This was reported by several workers. Naas (2013) commented that “The picrite has been interpreted to represent wedges of basalt that have been tectonically emplaced along major fault zones.”
Rhyodacite: This was reported only by Preto (1968).
Giles Peatfield
BASc. (Geological Engineering) University of British Columbia 1966.
PhD Queen's University at Kingston 1978.
Worked for Texas Gulf Sulphur / Texasgulf Inc. / Kidd Creek Mines - 1966 to 1985.
Vancouver based consultant 1985 to retirement in 2016

Other Databases

Link to British Columbia Minfile:	092INE007

Other Regions, Features and Areas containing this locality

References