Chicago workings, La France Creek, Nelson Mining Division, British Columbia, Canadai

Regional Level Types
Chicago workings	Workings (Abandoned)
La France Creek	Creek
Nelson Mining Division	Division
British Columbia	Province
Canada	Country

The Chicago occurrence is located at about 2300 metres (7,500 feet), on a ridge between La France and Baker creeks, about 10 kilometres east-northeast of the mouth of La France Creek on Kootenay Lake, or 48 kilometres east of Nelson, British Columbia, in the Nelson Mining Division.

There is a description of the property, including regional geology, on the British Columbia “Minfile” site, current to 2018. Relevant portions are quoted below:

“The area is predominantly underlain by a north trending sequence of argillite and quartzite units of the Middle Proterozoic Mount Nelson Formation (Purcell Supergroup). This assemblage abuts the older conglomerate unit of the Upper Proterozoic Toby Formation (Windermere Supergroup) to the west and sedimentary rocks of the Dutch Creek Formation (Purcell Supergroup) to the east.

Locally, laminated and massive dolomites and siliceous limestones host sphalerite, galena and minor tetrahedrite mineralization. The sulphide mineralization occurs as networks of veins, stringers and irregular pods with silica-carbonate alteration.”

Giles Peatfield indicates that there is no recorded production from this property.

Comments on the Minerals Reported:
Ankerite: Reported by Bullis (1973) from the Peg #9 claim, about 1 kilometre south of the original Chicago workings on the Montana Crown Granted claim.

Baryte: Bullis (1973) described minor barite [sic] with other minerals in the underground workings on the Montana claim.

Bournonite: This was first reported by Warren (1948), from the Chicago (La France Creek) property, based on X-ray analysis by Dr. R.M. Thompson, then at the University of Toronto. His comment was “A specimen labelled “tetrahedrite” from this property, supplied by the Department of Mines, Victoria, B.C., proved to be bournonite with galena in quartz.” Berry and Thompson (1962) listed this occurrence in the “Peacock Atlas”. The Pacific Museum of Earth at the University of British Columbia has a collection of specimens (#1912), presumably of the same material, which includes several small fragments of vein quartz and two polished sections.

Calcite: Bullis (1973) described calcite from the underground workings.

Chalcopyrite: First reported by O’Grady (1927), and by Bullis (1973), from the underground workings.

Galena: This was the main mineral of interest in the early days. O’Grady (1927) described it as “argentiferous”.

Limonite: Bullis (1973) described limonite in oxidized vein material. Presumably this was derived from the breakdown of pyrite.

Pyrite: Reported by O’Grady (1927), who made the curious comment that it was “cupriferous”, but offered no further explanation. Bullis (1973) described it from the underground workings.

Quartz: Warren (1948) mentioned quartz, and it is evident in the Museum specimens.

Sphalerite: O’Grady (1927) reported “zinc blende”; Bullis (1973) described sphalerite from the underground workings.

Tetrahedrite subgroup: Bullis (1973) reported “some tetrahedrite” from the underground workings.

Wad: I have used this generic term for the black Mn oxides described by Bullis (1973).

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 1982 to retirement in 2016

Other Databases

Link to British Columbia Minfile:	082FNE109

Other Regions, Features and Areas containing this locality

References