NR - Dec 10th 2015 Balmoral Reports Gold Recoveries of 91.4%
posted on
Dec 15, 2015 12:25PM
a 100% interest in 74,000 hectares of land in the historic Rouyn-Noranda Mining Camp
Balmoral Reports Gold Recoveries of 91.4% From Preliminary Metallurgical Testing of Bug Lake Gold Zones, Martiniere, Quebec7:30AM ET on Thursday Dec 10, 2015 by Marketwire
Balmoral Resources Ltd. ("Balmoral" or the "Company") (TSX: BAR) (OTCQX: BALMF) today announced that gold recoveries of 91.4% and silver recoveries of 80.2% have been achieved in preliminary metallurgical testing conducted on a composite sample comprised of material from the four principal gold bearing zones located along the Bug Lake Trend on the Company's Martiniere Property in Quebec. Results were achieved by standard flotation followed by cyanide leaching of the flotation concentrate and tails. The Bug Lake Composite sample was collected from previously drilled core holes. It was dominantly comprised of material from the Lower Bug Lake Zone, but included representative material from the Hanging Wall, Upper Bug Lake and Footwall Zones. The average assayed head grade for the Bug Lake Composite was 6.3 g/t gold and 7.1 g/t silver. The current metallurgical testing was performed on behalf of the Company by Blue Coast Research Ltd. of Parksville, British Columbia following an initial stage of work conducted by SGS Minerals in Lakefield, Ontario. "Today's results provide a very positive start to the metallurgical work on the Bug Lake Zones, indicating plus 90% gold recoveries" said Darin Wagner, President and CEO of Balmoral. "The preliminary work suggests there are no concerns regarding the blending of the multiple zones located along the Trend and indicates some room to potentially increase recoveries with more detailed testing now that general metallurgical parameters have been established. The very fast leach kinetics, potential to work with a relatively coarse grind, and lack of deleterious elements were additional positives from the testing." Metallurgical Testing Initial metallurgical testing consisted of direct cyanidation of the Bug Lake Composite using a series of grind sizes which would be typical of the industry. Direct cyanidation achieved gold recoveries of 72 to 81%, and silver recoveries ranging from 65 to 73%. In general, finer-grind sizes resulted in higher recoveries. Gravity recoveries ranged from 7.3% to 24.3% for gold, again increasing at finer grind sizes. Gravity recovery followed by cyanidation of the gravity tails achieved virtually identical results to direct "whole ore" cyanidation. Blue Coast conducted five flotation tests on the Bug Lake Composite; three to establish the optimal grind size and two to create concentrates for leaching. All three grind sizes tested produced similar gold (97%) and silver (92-93%) recoveries to concentrate. The coarsest grind -- 127 microns -- was selected for the leaching tests. Testing included separate and combined leaching of the flotation concentrate (after fine regrinding) and tails. Optimal recoveries were achieved from separate leaching of the flotation concentrate and tails. The table below summarizes the metallurgical balance for this scenario. Metallurgical Balance from Separate Concentrate and Tails Leach Option Leach testing of the flotation concentrate displayed very rapid kinetics with gold extraction peaking after only 3-5 hours. In general, cyanide consumptions during both the concentrate and tailings leach were very low and lime consumptions were also modest given the precious metal content in each product. Quality Control The technical information disclosed herein was prepared under the supervision of qualified person Mr. Chris Martin (C. Eng.) of Blue Coast Research Ltd. Mr. Martin has supervised the metallurgical work reported on and has reviewed and approved the technical disclosure contained in this news release with respect to such work. Mr. Darin Wagner (P.Geo.), President and CEO of the Company, qualified person for the Company, supervised the collection of the samples for metallurgical testing, reviewed the progress on the metallurgical testing on multiple occasions and has also reviewed and approved of the technical disclosure contained in this news release.----------------------------------------------------------------------------
Mass Gold Silver
% % %
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Feed 100 100 100
Flotation concentrate 20.4 96.1 92.5
Concentrate leach extraction n/a 88.9 74
Concentrate leach residue 20.4 7.2 18.5
Flotation Tails 79.7 3.9 7.5
Tails leach extraction n/a 2.5 6.2
Tails leach residue 79.7 1.4 1.3
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Combined circuit extraction n/a 91.4 80.2
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Extraction rates Gold, % Silver, %
Conc leach extraction rate 92.5 80
Tails leach extraction rate 65 83
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-- Note: rounding errors may lead to some numbers adding to over 100%