Virtual Museum ID: 19-HM-06
Bornite is an important copper ore mineral found in many different types of copper deposit. It is also known as peacock ore because of its iridescent purple-blue-green tarnish. Fresh bornite, however, is copper red. Bornite commonly occurs with other copper sulphide minerals such as chalcocite and weathers, or “oxidizes”, to malachite.
The information listed below relates to the current holding location or collection that the sample is from, and whether the item is viewable at that location or is part of a private collection. Coordinates are given as guides, and we remind you that collecting specimens from these locations is not allowed. Caution is advised visiting such sites and Below BC assumes no responsibility for any injuries or trespassing charges that may occur as a result of the viewer entering these sites.
Original Collection:Hedley Museum (HM)
Virtual Museum ID:19-HM-06
Date Added to VM:2019-06-05
Sample Origin:Hedley, BC
Specific Site:French Mine
Datum:10 (NAD 83)
Primary Mineral Formula:Cu5FeS4
Advanced Geological Information
The following section provides geological data relating to the specimen or the site it was collected from, when available. Information has been obtained from various sources including private and government datasets but may not be up to date. Any geological time periods or ages listed often relate to the primary geology of the area, and may not be the actual date of an event such as mineral formation.
Geological Formation:Apex Mountain Complex/eachland Creek Formation/Nicola Group
Geological Period:Ordovician to Triassic/Middle to Upper Triassic/Upper Triassic
Stratigraphic Age:485.4 - 201.8 Million Years Ago
The French mine is situated 1.5 kilometres northeast of the Similkameen River, 5.2 kilometres southeast of Hedley.
This area between Cahill and Winters creeks, along the northeast bank of the Similkameen River, is underlain by various sediments and volcanics comprising the Ordovician to Triassic Apex Mountain Complex, the Middle to Upper Triassic Peachland Creek Formation and the Upper Triassic Nicola Group. This sequence is cut by hornblende porphyritic diorite dykes and sills of the Early Jurassic Hedley Intrusions, and intruded by granodiorite of the Middle Jurassic Cahill Creek pluton.
The French mine is hosted in the French Mine Formation (Nicola Group), near the contact with the Cahill Creek pluton to the southwest. The formation locally consists of cherty tuffs, overlain by 4 to 6 metres of limestone and limestone conglomerate, which is in turn overlain by tuffs. These units are brecciated and skarn-altered along the hinge portion of a faulted anticline that strikes west to northwest. The alteration and associated mineralization is believed to be related to several dioritic dykes and sills that cut the mine area. The alteration consists of garnet, diopside and calcite, with variable quantities of plagioclase, wollastonite, clinozoisite, epidote, biotite, potassium feldspar, scapolite and quartz. Mineralogical zoning is evident, with an outer envelope of biotite hornfels passing inward into the later developed crosscutting garnet-diopside assemblages.
The mined orebody trends northwest, plunges southeast, but is flat lying for most of its length. Up to 1958, the deposit had been mined over a strike length of 190 metres and a dip length of 24 metres. Mineralization is terminated against the high angle French fault to the west and the west dipping, northeast-striking Cariboo thrust fault to the east. Other northeast and northwest striking high-angle faults have been identified underground, with displacements generally less than 3 metres.
Sulphides average less than 5 per cent by volume throughout most of the deposit, except for the western part, which is relatively rich in copper and low in gold. The skarn is mineralized with arsenopyrite, pyrite, chalcopyrite, covellite, bornite and pyrrhotite, and sporadic coarse molybdenite and scheelite, in zones up to 40 metres in length and 3 metres in width. Minor cobaltite, erythrite, tellurides and native gold have also been identified. Gold is reported not to be associated with sulphide mineralization, occurring free in association with bismuth telluride. A chip sample taken over 0.91 metre assayed 1179.2 grams per tonne gold (Vancouver Stockwatch July 11, 1989). Several other samples yielded values of over 34 grams per tonne gold over similar widths. Inferred reserves are estimated at 8731 tonnes grading 5.1 grams per tonne gold, 103 grams per tonne silver and 2 per cent copper (National Mineral Inventory - Westervelt Engineering Ltd., 1978).
A total of 77,608 tonnes of ore averaging 20.66 grams per tonne gold was mined from three levels of underground workings over an elevation of 41 metres by Kelowna Mines Hedley Ltd. and French Mines Ltd. between 1950 and 1961. Grove Explorations Ltd. and Dankoe Mines Ltd. produced 4438 tonnes in 1982 and 1983 grading 5.95 grams per tonne gold, 30.48 grams per tonne silver and 0.4627 per cent copper. The underground workings were sampled by Golden North Resource Corporation in 1989.