The Guindon occurrence is located on the western side of Moyie Lake, approximately 24 kilometres south of Cranbrook.
The area is underlain by clastic rocks of the Helikian Purcell Supergroup. The units are dominantly siliciclastic sedimentary rocks of the Lower and Middle Aldridge formations. In the southeast, the right-lateral reverse Moyie fault juxtaposes Aldridge rocks with a conformable package of younger Creston Formation siltstones and argillites. The Proterozoic Moyie Intrusions are gabbro sills and intrude the Lower Aldridge Formation and the lower part of the Middle Aldridge Formation. Regional metamorphism is upper greenschist facies.
Locally, a lead-zinc (galena-sphalerite) vein system up to 90 centimetres wide with an easterly strike and dipping about 60 degrees south is hosted by Helikian Middle Aldridge Formation (Purcell Supergroup) sediments. The vein is most likely a westerly extension of the St. Eugene fracture system (082GSW025) and related to the Aurora vein (082GSW023), 450 metres to the south.
The occurrence lies on the western limb of a northeast-plunging anticlinal structure and probably represents a tensional fracture across the crest of the anticline. Veins carry scattered small pods and lenses of galena, sphalerite, and pyrite in a quartz gangue.
In 2007, a single diamond drill hole (A-07-4) was completed in the Aurora area to test the western extension of the Aurora sulphide vein system. The hole was drilled to a total depth of 242.6 meters. The hole intersected a 0.75-metre vein zone consisting of quartz, calcite, and actinolite with minor pyrrhotite, pyrite, and sphalerite at a depth of 204 metres. Minor sphalerite and chalcopyrite are also reported along a healed fracture at 195 metres depth (Assessment Report 29809).
The workings produced 28 tonnes of ore in 1919, 1923 and 1927, resulting in 3328 grams of silver, 3494 kilograms of zinc, and 3312 kilograms of lead (BC METAL MM00529).
WORK HISTORY
The Aurora group, comprising the Etna, Durango, Aurora, Horseshoe and Portland claims (Lots 7015-7017, 7022, 7205 respectively) was owned from 1898 or earlier by I.B. Sanborn of Portland Oregon and associates Messrs. Johnson and Rader. Development work was begun in open cuts and a drift adit. The claims were Crown-granted in 1906. Aurora Mining and Milling Company, Limited, incorporated in 1908, acquired an option on the property and development work continued into 1910. The workings included 3 adits totaling about 290 metres of drift and crosscut. Between No. 2 and 3 adits a shaft was sunk 24 metres with 55 metres of drift to the west. Five claims staked adjoining on strike to the west (Lots 2167-69, 2330, 2331) were Crown-granted to F. Guindon, J.A. Harvey and associates in 1910; no development work is reported on these claims. The Guindon, Ferole, and Alice Fr. claims (Lots 6127, 9806, 1907 respectively), located adjoining the Aurora group on the north, were Crown-granted to F. Guindon, J. Gosselin and associates in 1914. By 1923 the workings included about 290 metres of drift and crosscut in 2 adits on No. 1 vein, and a 122 metres of drift adit on No. 2 vein. St. Eugene Extension Mines, Limited was incorporated in 1929 to acquire the Guindon group, an option on the Aurora, and a lease on the St. Eugene. A winze was sunk from the Aurora No. 2 adit and the upper (No. 3) adit was extended. St. Eugene Mining Corporation, Limited was incorporated in 1939 to acquire the holdings of the former company. A geological survey was carried out and some of the adits on the Aurora and Guindon groups were re-opened and examined. Diamond drilling was done in 2 holes on the Aurora in 1940.
In 1947, Saint Eugene Mining completed a program of geological mapping and a 10 line-kilometre ground magnetic survey on the area as the Moyie property. St. Eugene Mining Corporation carried out joint exploration in 1962-1963 with Consolidated Mining and Smelting, owner of the St. Eugene property on the east side of the lake. Falconbridge Nickel Mines, Limited in 1965-1966 carried out geophysical and geochemical surveys and diamond drilling under an agreement with the above companies. The 1960s work was confined mainly to the east side of the lake.
In 1990, Cominco completed a 16.5 line-kilometre ground electromagnetic survey on the area. In 2006, Saint Eugene Mining completed 697 line-kilometres of airborne combined magnetic and electromagnetic surveys over 2 grids that covered the St. Eugene (082GSW025), North Zone (082GSW086), Guindon (082GSW027), Aurora (082GSW023), Fors (082GSW035), and Smoker (082GSW041) (Assessment Report 28450). Several weak conductors possibly associated with mineralization were reported. In 2007, St. Eugene Mining completed a lone drillhole, totalling 242.6 metres.