Abcourt-Barvue

Overview

The Abcourt-Barvue zinc-silver mineral property covers 3,452 hectares and is located in BarrauteTownship in northwestern Quebec, Canada. 

Silver-zinc mineralization was first discovered in the region in 1950 by Dr. W.W. Weber from the Quebec Department of Mines. A staking and prospecting rush ensued in the region. Mineralization on the property was discovered during the same year by prospector Gerard Leclerc who found a zinc-silver showing grading 3.62 % Zn and 188.7 g/t Ag over 6.7 metres in one of his trenches. 

The Barvue deposit was Quebec’s most important zinc producer in the 1950s. It was open pit mined in the period 1952 to 1957 when it produced 5 million tonnes grading 38.74 g/t silver and 2.98% zinc. In the period 1985-1990 ore was extracted from underground in an operation that yielded 0.632 million tonnes grading 131.65 g/t silver and 5.04% zinc. 

The Abcourt-Barvue mineral deposits are 100% owned by Abcourt Mines Inc. The company plans to develop a mining operation consisting of a series of three open pits (Barvue being a pit expansion) and development of an underground mine. 

Mine life is estimated at 10 years. 

A 1,800 tonnes per day mill is to be constructed at the mine site. Crushing, milling, cyanidation and flotation are processes involved in the production of precious and base metals concentrates. Ingots would be shipped to a precious metals refinery inCanada and zinc concentrates would be shipped to a custom smelter.

Location

Quebec is a large Canadian province whose official language is French. 

The name of Quebec - name derived from the Algonquin ‘kebec’ meaning  â€˜â€™where the river narrows’ – was chosen by French explorer Samuel de Champlain in 1608 for the settlement that would be used as seat for the French colony of New France. 

The province of Quebec is endowed with many natural resources mineral deposits included. Over half of the province is covered by forests. The province also boasts over a million lakes and rivers that occupy 21% of its territory. 

The Abcourt-Barvue property can be easily reached all year round from Val-d’Or via highway 397 and by range road 6-7 to the mine site, about 5.5 km north of Barraute. 

The project site is a relatively flat plateau made of grayish glacial clay and till with occasional ridges of rocks and glacial debris (eskers oriented predominantly north-south) that are cut by many streams.  Elevation averages 35 m and reaches a maximum of 100 m. 

Climate is continental characterized by cold winters (-10 deg C to -35 deg C) and moderate summers (10 deg C to 22 deg C). Average snow cover measures 83 cm and summer precipitations total 115 mm of rain. 

Laflamme river runs north through the property.

Geology and Mineralization

The Abcourt-Barvue deposit is part of the Abitibi geological subprovince made of typical granite and greenstones rocks located in the south-eastern part of the Superior province of theCanadian Shield. 

The Abcourt-Barvue silver-zinc deposit is considered to be of a disseminated volcanogenic sulphide deposit type that is similar with the Mattabi-type volcanogenic sulphide deposit. It is hosted by a volcaniclastic sequence consisting of tuffs and agglomerates that are carbonatized and sericitized. 

Zinc and silver are the main metallic constituents of the deposit and are associated with sphalerite, native silver, argentite and pyrite. Gold is associated with silver and copper and occurs mostly in the eastern part of the deposit. 

Mineralization is thought to have been formed near surface close to a local marine basin and it is related to felsic volcanism. It is possible that it was later remobilized during one of the tectonic episodes that affected the region. 

Mineralized zone has a thickness ranging from 2 to 30 m and a known east-west strike length of 2.2 km. Underground ore is found in the hanging wall of a marker tuff horizon. 

The undiluted measured and indicated mineral resources are 7 million tonnes grading 61.19 g/t silver and 3.33 % zinc.

Mining & Operation 

Mining would be carried out using a conventional open pit mining method for 83% of the tonnage with the balance of ore planned to come from underground mining operations starting with the 6th year of operations. 

The company plans to develop a conventional mining operation consisting of a series of three open pits (Barvue being a pit expansion). Overburden is 2 to 6 m thick at the Barvue pit and about 10 m over the Abcourt pits. Average stripping ratio is 6.42:1. 

Haulage trucks from both the open pits and underground works would dump ore to the ore mixing area near the crusher. 

Orefrom the pits would be exhausted in 8 years at 650,000 tpa milling rate. Starting with the 6^th year underground ore would add to the production. Underground production would reach 324,000 tpa in year 8. 

For open pit blasting it would use one conventional in-the-hole 152 mm or 203 mm hammer rig for waste drilling and a 76 mm crawler drill and compressor for ore. Loading would be effectuated by 6.8 m3 front-end loader in waste and a 3.5 m3 hydraulic backhoe shovel in ore. Another 6.8 m3 wheel loader would be used as back-up. A fleet of five 62-t capacity trucks would be used to haul ore and waste rock. 

Supporting equipment include two 240 KW bulldozers, one 2m3 hydraulic shovel mounted with a scaling bar, and one water truck. 

Dewatering of pits and underground mine would be done by employing stationary and submersible pumps. A water treatment plant would treat it before discarding.

Underground ore is found in areas characterized by good ground conditions so the Avoca cut-and-fill method can be employed in mining the mineral resource.  Cross cuts would be driven in the ore body from three main declines; sub-levels would be developed at 15 to 20 m vertical intervals. 

Mining would be trackless: jumbos and remote controlled 5 or 2 cubic yard scoops would be used for loading. Benches would be drilled with longhole machines. 30-t trucks would haul the ore to the surface and would bring back waste rock for backfilling purposes if necessary – main backfill would be mill tailings and/or pyrite concentrate.

Process 

The process plant was designated at 1,800 tonnes per day capacity.Oreis mixed and blended on a platform before being fed to the crusher and the SAG mill for grinding. 

A cyanidation circuit would recover the silver first through a Merryl-Crowe method and calcination and smelting. Final products are silver-gold ingots that are going to be sent to a precious metals refinery in Canada. 

After washing and aeration the pulp would be directed to a flotation circuit. Zinc and silver concentrate would be first obtained after running the pulp through a conventional rougher-scavenger-cleaner circuit. Zinc-silver concentrate would be trucked first, then railed and shipped to custom smelters. 

Rejects would be directed to the pyrite flotation circuit that would separate pyrites from the rest of the non-acid generating tailings. The pyrite concentrate would be used as backfill in the underground mining operations.

Environment & Community

Company’s environmental management program was designed to meet or surpass standards and regulations. 

The local population and economy would definitely benefit from the opening of the Abcourt-Barvue mine.