Name: Lapa mine.
Location: The Lapa mine is located in the Abitibi region of north-west Quebec, 11 km east of Agnico-Eagle’s LaRonde mine, in Canada.
Controlling Company: Agnico-Eagle Mines (100%).
Brief Description: Lapa is Agnico-Eagle’s highest-grade mine, with gold grades almost twice as rich as the company’s average. There are 130 people employed at the mine. The mine’s life is expected to end in 2015.
Brief History: In 1933, gold mineralisation was reported from the first exploration drill holes to test the property. From 1937 to 1943, Lapa Cadillac Mines extracted almost 50 000 oz of gold. The mine was later closed, owing to wartime labour shortages and gold-recovery problems. Breakwater Resources conducted an exploration programme from 1981 to 1988 that culminated in an exploration ramp to test the underground Highway zone. After optioning the property from Breakwater Resources in 2002, Agnico-Eagle initiated a diamond-drilling exploration programme and metallurgical testwork, which involved sinking a new mine shaft. Agnico-Eagle acquired 100% ownership of the Lapa mine in 2003. A feasibility study was conducted in 2006 and the company was awarded the exploration rights to the property. Production began in 2008. The Lapa processing plant started in April 2009. Gold was first poured at Lapa on May 7, 2009. The mine had its opening ceremony in August of the same year.
Mining Method: Underground.
Major Infrastructure and Equipment: Lapa is accessed by a 1 369-m-deep shaft. Two mining methods are used – longitudinal retreat with cemented backfill and locally transverse open stoping with cemented backfill. In longitudinal retreat, sublevels are driven at 30 m vertical intervals, linked by a ramp. Stopes are mined in 12 m sections along the length of the orebody, with variable widths using a pyramidal sequence and backfilled with 100% cemented rockfill. In transverse open stoping, all the ore is mined across the width of the orebody and filled with cemented rockfill. The ore is hauled on 77 level and 125 level. The average dilution for mining the reserves is expected to be 50%.
Geology: The Lapa property straddles the Cadillac-Larder Lake fault zone, a regional structure that hosts numerous gold prospects and past producers, including the Macassa and Kerr Addison gold mines.
The fault zone is taken up by the Archean-age Piché Volcanic Group rocks, which are locally folded. Many of the gold-mineralised zones are located in the hinges of the fold structures.
Gold mineralisation at Lapa is located in zones of deformation within the Piché Group volcanic rocks. Gold is known to occur in three styles: as quartz veins, as tabular zones or as biotite-altered zones. The contact zone is potentially an economic lens of mineralisation that has been traced for up to 600 m horizontally and more than 1 000 m vertically. The zone is currently open at depth in all directions.
Reserves: Total proven reserves, as at December 31, 2012, were 1.129-million tonnes, with a grading of 6.25 g/t gold. Total probable reserves were 939 000 t, with a grading of 5.58 g/t gold.
Resources: Total indicated resources as at December 31, 2012, were 1.118-million tonnes, with a grading of 4.08 g/t gold, while total inferred mineral resources were 934 000 t, with a grading of 6.69 g/t of gold.
Prospects: In 2012, Agnico completed excavating exploration drifts to the east and west of the existing mine workings at a depth of about 1 000 m. These drifts will serve as a platform for the majority of the exploration drilling at Lapa in 2013. The goal is to extend the mine’s life beyond 2015.
Contact Person: Corporate communications.
Agnico Eagle Mines
Tel +1 416 847 8669
Fax: +1 416 367 4681
Edited by: Creamer Media Reporter
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