Bornite

Specimen Summary

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.

This sample is from the Silver King mine about 7 km south of Nelson in the Kootenay region of southeastern BC.

The Silver King mine was active between 1896 and 1949. In that time, it produced over 200,000 tonnes of ore at grades of 672 grams per tonne silver, 0.5 grams per tonne gold and 3.2% copper. It was once Nelson’s largest mine, putting the town on the map as one of BC’s major silver mining centres. A mining camp, the Silver King Camp, was also home to about 200 people at the mine site, but it was burned down in the early 1900s in a forest fire.

The property was discovered in 1886 by the Hall brothers, who were prospecting for placer gold. They staked three claims: Kootenay Bonanza, Silver Kings and American Flag. The first high-grade ore was shipped in 1889. Initially, ore was transported down the mountain by a process called raw hiding. This was a very dangerous job for the men that transported the ore down! Ore was wrapped in cow hides, hair side down, and attached to a length of rope and pulled down the mountain by horse. A rider sat on the last hide in the train, attempting to control the speed and direction of the hide train using chain brakes. Trails were often icy and extremely slippery, making it very difficult to control the loads. Thankfully a tramway was soon built to transport the ore instead!

In 1893, Hall Mines Limited purchased the property and developed the underground workings and a tramway to transport ore to Nelson for smelting. A 100 tonne-per-day smelter was opened in town in January of 1896. Mining continued until 1919, with small operations in 1936, 1946-1949, 1956 and 1958. Exploration has continued intermittently since then. For several years in the 1960s and early 1970s the slope around the mine hosted a ski hill. The founders of that ski hill eventually went on to establish the Whitewater hill, still open today.

The ore at Silver King is mainly in veins that run parallel to a shear zone, or faulted deformation zone. The veins contain pyrite, chalcopyrite and galena (lead ore), with minor amounts of sphalerite (zinc ore), bornite (copper ore), malachite and azurite (secondary copper minerals), and stromeyerite, as seen in this sample. The main gangue (waste) mineral is quartz, with minor carbonate.

Specimen Data

 

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.

Collection Details

Original Collection:

Chamber of Mines of Eastern BC (NCM)

Sub Collection:

-

Collection ID:

NCM_07

Virtual Museum ID:

19-NCM07

Accessibility:

Date Added to VM:

2019-06-11

Location Information

Sample Origin:

NNW of Peachland, B.C.

Specific Site:

Silver King

UTM Easting:

286349

UTM Northing:

5520284

Datum:

11 (NAD 83)

Coordinate Accuracy:

Approximate

Specimen Details

VM Category:

Mineral

Primary Features:

Bornite

Primary Mineral Formula:

Cu5FeS4

Primary Category:

sulphide

Secondary Features:

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:

Pennask Batholith

Geological Period:

Early Jurassic

Stratigraphic Age:

174.1 to 201.3 Million Years Ago

Geological Belt:

Intermontane

Geological Terrane:

Plutonic Rocks

Minfile ID:

082ENW018

Minfile Link:

http://minfile.gov.bc.ca/Summary.aspx?minfilno=082ENW018

Site Details:

The Silver King mine is located approximately 16 kilometres north-northwest of Peachland. The area is underlain by granodiorite of the Early Jurassic Pennask Batholith. Outcrops of Triassic- Jurassic Nicola Group sedimentary and volcanic rocks occur approximately 500 metres to the northeast.

Work on the property dates back to the late 1890's when underground development work was commenced by the Canadian-American Mining and Development Company. As of 1898 the workings consisted of a 4.5-metre shaft, a 33-metre tunnel and a 6-metre crosscut on the shear zone. Also constructed on this shear was an 8-metre winze with a 12-metre crosscut. Gold in quartz veins, in a shear zone, was reported to be free milling (Minister of Mines Annual report 1898, page 1130). Limited production is recorded during the period 1939 to 1941, when a total of 244 tonnes of ore were mined which yielded 15,116 grams of silver and 1,618 grams of gold (Minister of Mines Annual Report Index No. 3, page 213).

In 1963, molybdenite is reported to have been discovered in old waste dumps in the area by R. S. Taylor and J. E. Nott. The area, including the Alma Mater (082ENW017) and the Silver King occurrences, was subsequently staked as the Rat No. 1-26 and the Big Daddy No. 13 mineral claims for Orville Burkinshaw. Trenching and test-pitting was carried out in the vicinity of the old workings in 1964. The results of this program were not recorded; however, it was observed that mineralization consists of threads and stringers of molybdenite with sparse coarse pyrite and rare chalcopyrite. All of the mineralization was associated with a white, siliceous, fine-grained but unevenly textured rock locally termed "white rock". In thin section, the rock was seen to be comprised chiefly of quartz with much altered plagioclase, carbonate, and phlogopite mica with lesser apatite and cordierite.

In 1965, Dr. M.C. Robinson, in a report for King Resources Ltd. notes that there was little evidence of work since the 1890's and that the lack of stoping in the workings suggest that the shipped tonnages, if any, cannot have been significant. In 1965, the workings consisted of an adit collared in granodiorite and in a zone of northerly trending and southerly dipping shearing. Quartz with pyrite and minor very fine-grained grey sulphides including galena are present along the slips and disseminated in the shear and wallrock. A crosscut driven northeasterly from a point 21 metres from the portal follows a shear containing small veins, lenses, and masses of quartz, quartz-pyrite and solid pyrite. The innermost 27 metres of the tunnel explores a strong zone of shearing 0.3 to 1.2 metres thick. The zone strikes northerly and dips to the east at 50 to 65 degrees. It is composed largely of gouge and crushed rock. The zone is poorly to non-mineralized, except for quartz and minor amounts of pyrite.

In 1967 Anuk River Mines Ltd. carried out geological and geochemical surveying, trenching and 305 metres of diamond drilling in 3 holes. The geochemical survey did not produce anomalies. Mineralization in the drill core was sparse and consisted of black sphalerite with minor amounts of chalcopyrite and pyrite. The hostrock in all three holes was sheared quartz diorite, or granodiorite, with few or no quartz veins but containing epidote, calcite and chlorite seams and veinlets.

In 1978, Brenda Mines Ltd. restaked the area, including both the Alma Mater (082ENW017) and the Silver King showings, as the Greata III to V and Greata IX and X claim blocks. Geological and geochemical surveys done in 1978 were followed up by an I.P. survey and exploration drill program in 1979. Two diamond-drill holes, for a total of 79 metres, were drilled in the vicinity of the Silver King to test the extent of a sericitized diorite. The results were discouraging, only traces of molybdenum were encountered and the sericite alteration zone was found to be only 9 metres thick (Assessment Report 7872).

In 1986, Cordilleran Engineering staked the Oka 1 - 11 claim block, which included the Silver King and Alma Mater showings, for Fairfield Minerals Ltd. Their exploration program in 1986 included prospecting and sampling of the Silver King showing. Grab sample assays returned silver values as high as 68 grams per tonne (Assessment Report 15834). Gold assays were uniformly low. Details of sample mineralogy are lacking, as are base metal assays, but the highest silver values were from samples collected in the vicinity of the shaft. The work for Fairfield Minerals was mainly focused on gold occurrences to the east, including: Bolivar West (082ENW098), Bolivar East (082ENW099), Bolivar Road (082ENW100), Bolivar Creek (082ENW101), Iron Horse (082ENW025), and Cap (082ENW026).

Additional Images