The Langis Mine (past producer of high-grade silver) project is located near Cobalt in eastern Ontario, 15 km north from Temiskaming shores and 500 km north from Toronto. Highway 65 runs through the property and many secondary roads are established providing year round access. Power, railways, mills, a permitted refinery and assay lab are located in or near the site.
The Langis project represents unique opportunity to a silver district that has not seen much modern exploration techniques applied. New discovery potential is high and a strong possibility exists to generate mineral resources from extensions to historical workings and new exploration.
The Langis Mine has produced historically over 10.4M oz Ag with a recovered grade of ~25 oz/t Ag from shallow depths. (see production history)
The Langis project does not currently contain any mineral resources or mineral reserves.
July 2016 Drilling Maps
Langis Mine Ore (photo source Cobalt Museum, Thompson 2015)
Silver recovery estimates range from 88% to 98% based on historical records. IP resistivity and chargeability surveys over the Langis area by Canagco in 2012 image variably elongated and steeply dipping apparent structures. Drill testing will be needed to confirm that targets are hosting mineralization. Favorable geology exists for gold mineralization related to shear zones and syenite intrusions in the northern area of the project not previously explored.
The Langis project will benefit greatly from new knowledge and different views and the use of 3d modelling. Basement structures offer new discovery potential for both silver & gold.
Langis Assay Results:
|Drill hole ID||From (m)||To (m)||Interval (m)||Weighted Average Au (g/t)||Weighted Average Ag g/t||Comments|
|LM-16-01||0||153.76||Results released on August 11, 2016|
|LM-16-02||0||168.83||No significant results|
|LM-16-03||156.05||160.20||4.15||4.90||397.00||Results released on August 11, 2016|
|including||158.20||158.42||0.22||74.9||5236.40||Results released on August 11, 2016|
|LM-16-03||179.41||182.54||3.13||-||1944.60||Results released on August 11, 2016|
|including||179.41||180.61||1.2||-||3527.50||Results released on August 11, 2016|
|including||181.88||182.08||0.2||-||6350.00||Results released on August 11, 2016|
|LM-16-05||0||148.93||Encountered an underground opening|
|LM-16-06||0||200.39||No significant results|
|LM-16-07||0||160.87||160.87||Encountered an underground opening|
|LM-16-08||0||359.06||No significant results|
|LM-16-12||0||257.71||No significant results|
Brixton Metal’s mineral title holdings in the Silver-Cobalt Camp is 3,364 hectares. The high-grade silver mineralization occurs as steeply-dipping veins within any of the three main rock types: Archean volcanics, Coleman Member sediments and Nipissing diabase.
Historical Langis Drill Intercepts
|Drill ID||Grade oz/t Ag||Interval feet||Grade g/t Ag||Interval metres|
Archean Keewatin: These rocks comprise both metavolcanics and metasediments. The volcanics are most commonly intermediate to mafic pillowed and massive flows. Between flows, deep-water sedimentation prevailed with cherty and pyroclastic sediment laid down. These interflow sediments are commonly rich pyrite, pyrrhotite, chalcopyrite, galena, and sphalerite. Throughout the area, the volcanics are intruded by various mafic and ultra-mafic dikes.
Algoman: A large hornblende syenite pluton intruding the mine property host potential for gold mineralization but has yet to see much exploration attention.
Proterozoic: Huronian Supergroup: Huronian rocks comprise the majority of exposed outcrop on the Langis property and consist of gently-dipping, unaltered clastic, glacially-derived sediments unconformably overlying the older Keewatin volcanic and intrusive rocks (Lowes, 1963).These sediments form the Coleman Member of the Gowganda Formation and consist of para- and ortho-conglomerates, pebbly sandstone and greywacke, and thinly-bedded argillites.
Early Proterozoic (Keewenawan): Rocks of this age are represented by the Nipissing diabase sill, a prominent and important rock type in the Cobalt Basin. The diabase intrudes in the form of extensive sheets as well as less prominent dikes and plugs.
The earliest structural event resulted in isoclinal folding of Keewatin volcanics and interflow sediments during the Kenoran Orogeny 2.5 billion years ago (Jambor, 1971a). Precambrian faults, fractures,and joints observed within the mine exhibit variable dips.
Regional faults occur as prominent north to northwest structures which extend for hundreds of kilometres and weak northeast-trending sets (Andrews et al., 1986). Many smaller faults are present locally and are likely related to these large-scale faults. The major faults are believed to have been active in late Archean times; before, during, and after Huronian sedimentation; and during and after intrusion of the Nipissing diabase (Andrews et al., 1986). Post-diabase activity is considered to be a possible mechanism for creating the structures hosting the silver-cobalt vein systems which are so important to the Cobalt camp (Andrews et al., 1986).
Generally, distribution of this alteration is within approximately 100m of the Nipissing diabase contacts wherever necessary conditions occur (Jambor, 1971d). Carbonate is the most common gangue as calcite and dolomite and quartz is associated with the veins.
Owsiacki (1988) indicates:
“Significant high‐grade silver intersections have been recovered from within all three rock types being Nipissing Diabase, Coleman sediments, and, Archean volcanics at the western margin of this trough. One of the best assay to date is 50 ounces over 9.45 m, intersected in the volcanic rocks.”
The most important ore mineral is native silver and secondary metals are cobalt, nickel and copper.
All silver bearing veins in the Langis Mine area are steeply-dipping and are categorized as either single-vein or multiple-vein type structures (Jerome, 1969).
SILVER CAMP HISTORY
The camp produced historically over 420Moz of silver. One of the reported mine workings from the Cobalt camp reached 255,146 g/t Ag or 9,000 oz/t Ag over 0.36 metres. This single stope at the 30m level on this vein produced 4.5Moz Ag.
The picture to the right shows some of the headframes established within the Cobalt mining camp (photo source: Cobalt museum). While today most of the mine sites have been reclaimed or are under ongoing reclamation.
Silver was discovered at Cobalt in 1903 while the Timiskaming and Northern Ontario Railway was being constructed from North Bay to develop the agricultural land in the New Liskeard area. Fred LaRose, a blacksmith employed in the construction of the railway, is credited with the first discovery, but the first application for claims, filed on August 13, 1903, was made by J.H.McKinley and E.F.Darragh, subcontractors who supplied ties for the railroad. They found silver-bearing float at the south end of Cobalt Lake. The first assay results showed bismuth but no silver. McKinley subsequently sent the ore for assay to McGill University, and was informed by Dr. Milton Hersey of Montreal that the ore contained 4,000 ounces of silver per ton. Dr. Willet G. Miller, Ontario’s first provincial geologist, visited the area in November 1903 and found that four veins had been located, three very rich in silver. In addition, Tom Hebert had staked the property that later became the Nipissing Mine. Dr. Miller reported the news through an article in the Mining Journal of New York and through an Ontario Bureau of Mines publication. The final discovery in 1903 was made by Neil King who staked the property on which the O’Brien mine was to rise in 1906 and to continue production without a break until 1966 (Zoldy 2006).
Information Sources: Cobalt Museum Thompson 2015; Technical Report on the Langis Project by Dale R. Alexander, P.Geo, May 17, 2013; Approved Filing Statement for Everfront Ventures Corp July 31, 2013; Annual Report, Agnico Eagle Mines 1987; Interim Report, Agnico Eagle Mines Q2-1986; Agnico Eagle Mines, Langis Mine-New Mine Site, Plan & Section 1987;