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Monday, January 11, 2010
Gold in Canada: Bravo Reports Gold Recoveries from 87% to 92% in Metallurgical Test Work at Homestake Ridge BVG.v, GG, NEM, ABX, GDX, GRC.to, RR.v, PG
Posted by andre at 10:44 AMBravo Ventures is moving up from low band channel with signal Buy on Volume and all other indicators in neutral to positive (Slow STO). We have another important piece in this developing Gold deposit in Canada today - positive metallurgy. Last financing and dilution has brought a speed bump for this play, rising gold price and coming new encouraging drilling results will overcome it with a new highs this season.
"We are in agreement that it is time to rotate into Junior mining sector. After this consolidation, once investment public will realise that Gold will stay above 1000 USD/oz and it was not a final blip, money will go into Juniors, which still lack as a sector previous excitement of Bull Legs Up. Silver moves will be more dramatic, as usual, with double drivers of Inflation and Commodity High Tech Recovery play.
Economy is not rosy at all, but it is our ticket to the Growth. There is always Bull market somewhere. Debts could be only inflated away, do not bet on the Green Fellow - that this counter rally is for real. Orderly decline for Us Dollar is the name of the game.
Gold recent top coincided with Chinese calling for a Gold Bubble - they will be the buyers and keep it above 1000 USD/oz in a few months from now. Central banks become a Buyers in the Gold market with China, India and Russia now increasing positions. It will be the new driver."
Economy is not rosy at all, but it is our ticket to the Growth. There is always Bull market somewhere. Debts could be only inflated away, do not bet on the Green Fellow - that this counter rally is for real. Orderly decline for Us Dollar is the name of the game.
Gold recent top coincided with Chinese calling for a Gold Bubble - they will be the buyers and keep it above 1000 USD/oz in a few months from now. Central banks become a Buyers in the Gold market with China, India and Russia now increasing positions. It will be the new driver."
Press Release Source: Bravo Venture Group Inc. On Monday January 11, 2010, 1:31 pm
VANCOUVER, BRITISH COLUMBIA--(Marketwire - 01/11/10) - Bravo Venture Group Inc. (TSX-V:BVG - News)(Frankfurt:B6I - News) announced today that calculated gold recoveries ranging from 87% to 92% were returned from initial metallurgical testing on composite samples from its Homestake Ridge Project, NW British Columbia.
The company reported that the test work, which was conducted on a blend of composites from three different areas in the Main Homestake deposit, involved combinations of gravity separation, flotation, whole ore cyanidation and concentrate cyanidation to derive four separate process flowsheets. These resulted in calculated recoveries of 87% to 92% for gold and 59% to 70% for silver.
Gravity recovered 35% of the gold and 20% of the silver into a gravity concentrate. Lock-cycle flotation tests on gravity tails yielded gold, silver and copper recoveries of 85%, 84% and 95%, respectively, while direct cyanidation of gravity tails yielded gold and silver extractions of 87% and 49%, respectively.
Rougher flotation of gravity tails yielded 92% gold and silver recoveries into a rougher flotation concentrate. Cyanidation of reground rougher flotation concentrate yielded gold and silver extractions of 88% and 60%, respectively.
Metallurgical work is being conducted at SGS Lakefield Research Limited under the supervision of Melis Engineering Ltd. of Saskatoon, Saskatchewan.
President Joe Kizis comments, "We are pleased that our initial metallurgical test work has verified our belief that metal recovery should be quite attractive. Further optimization is necessary, of course, but several acceptable recovery options are available. Metallurgical test work continues, particularly on the Hangingwall Silver horizon portion of the Main Homestake deposit, and we are planning to initiate test work on our new discovery, the Homestake Silver deposit."
Detailed Discussion of Results
Composite 'HR'
Test work was conducted on Composite 'HR', a blend of three sub-composites from the Main Homestake deposit, which was chosen to test both significant head-grade and to approximate the average mineralogical properties of much of the Main Homestake deposit. The sub-composites, which sampled over 235 metres of mineralized interval, represented higher-grade sulphide-rich mineralization from two different areas of the deposit and shallow, lower-grade siliceous mineralization from a third area of the deposit. The analyzed head grade for Composite HR was 6.24 g/t gold 12.7 g/t silver and 0.14% copper.
Mineralogical work on samples from Composite HR, which included Scanning Electron Microscopy, revealed that the samples consists mainly of potassium feldspar (35.2%), quartz (27.5%), and moderate amounts of calcite/dolomite (7.8%), sulphides (less than 8.0%), clays (3.2%), chlorite (2.4%), and other minor components. Chalcopyrite, which accounts for most of the copper in the sample, is a minor component at 0.5%. Trace amounts of other sulphides, such as sphalerite, galena, arsenopyrite and pyrrhotite, are also present. Pyrite makes up 92.3% of the sulphides.
Gold is present as free particles, and attached or locked in particles of pyrite and silicate minerals. Numerous gold grains, some as large as 100 to 150 microns, were observed.
Silver is present as native silver, electrum, krustelite, hessite, silver tetrahedrite, acanthite, pyrargyrite, and as an alloy with antimony.
Process Options
The test work considered four process flowsheets, all incorporating gravity recovery at the front end of the circuit. These included:
�
-- Option 1 - gravity recovery then flotation of gravity tails to produce a
gold/silver concentrate with low copper values for sale to a smelter
-- Option 2 - gravity recovery then on-site dore smelting of gravity
concentrate and flotation of gravity tails to produce a gold/silver
concentrate with low copper values for sale to a smelter,
-- Option 3 - gravity then whole-ore cyanidation and dore production on
site,
-- Option 4 - gravity then flotation of rougher concentrate and cyanidation
of gravity and rougher concentrate and Dore production on site.
Metallurgical Efficiencies
Gravity recovery yielded 35% of the gold and 20% of the silver into a gravity concentrate representing approximately 0.05% of the feed weight. Gravity tails thus contained 65% of the gold and 80% of the silver.
Lock-cycle flotation tests on gravity tails yielded gold, silver and copper unit recoveries of 85%, 84% and 95%, respectively, into a concentrate representing 4.5% of the feed weight. The overall gross recovery of a gravity/flotation circuit was thus estimated at 90% for gold, 87% for silver and 95% for copper.
Direct cyanidation of gravity tails yielded gold and silver extractions of 87% and 49%, respectively, representing overall gross recoveries of 92% for gold and 59% for silver for a gravity/cyanidation circuit.
Rougher flotation of gravity tails yielded 92% gold and silver recoveries into a rougher flotation concentrate representing 20% of the feed weight. Cyanidation of reground rougher flotation concentrate yielded gold and silver extractions of 88% and 60%, respectively, representing gross overall recovery values of 88% for gold and 64% for silver for a gravity/flotation/cyanidation circuit.
Flowsheet Comparison
Based on the metallurgical test results and a composite head grade of 6.24 g/t gold, 12.7 g/t silver and 0.14% copper, the estimated recoveries for each of the four process options are summarized as follows. Note that recoveries listed in Options 1 and 2 assume that the concentrate is marketable (an assessment of potential smelters will form part of the on-going work for the project) and include deductions for typical copper concentrate smelter payment terms to make the values comparable to recoveries from cyanidation.
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Table 1
Bravo Venture Group Inc. - Homestake Ridge Project
Estimated Recoveries for Different Process Options
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% Recovery Estimate
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Process Option Au Ag Cu
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1 87 69 60
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2 88 70 60
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3 92 59 0
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4 88 64 0
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Option 1 - Recoveries listed include deductions for typical copper concentrate smelter payment terms for gold, silver and copper assuming the combined concentrate is saleable, based on a combined concentrate representing 4.5% of the feed weight and a calculated concentrate grade of 125 g/t gold, 245 g/t silver and 3.0% copper. These recovery values do not include any deduction for concentrate treatment charges, penalty charges or transportation costs.
Option 2 - Recoveries listed include deductions for typical copper concentrate smelter payment terms for gold, silver and copper assuming the flotation concentrate is saleable, based on a flotation concentrate representing 4.5% of the feed weight and a calculated concentrate grade of 70 g/t gold, 175 g/t silver and 3.0% copper. These recovery values do not include any deduction for concentrate treatment charges, penalty charges or transportation costs.
Test work Composite HR is essentially complete except for some tailings analyses and a detailed concentrate analysis, which is due in early 2010.
Composite 'SZ'
Test work was also begun on Composite 'SZ', a fourth and mineralogically distinct sub-composite of samples from the Hangingwall Silver horizon of the Main Homestake deposit, and will be completed in early 2010. It will include lock-cycle testing to quantify flotation recoveries under conditions approaching steady state, and mineralogical examination of the composite to determine the mode of occurrence of silver and gold. The assay for this composite is 12.4 g/t gold, 1,366 g/t silver, 0.07% copper, 0.4% lead and 0.91% zinc.
The mineralogy of Composite SZ is similar to mineralization identified in the newly discovered Homestake Silver deposit, which is located approximately 700 metres to the southeast of the Main Homestake deposit and was the focus of recent drilling by Bravo at the Homestake Ridge Project.
About Bravo Venture Group Inc.
Bravo Venture Group Inc. is focused on exploring its precious and base metal-rich Homestake Ridge project in British Columbia, a gold-rich epithermal/VMS-related system within Eskay Creek/Silbak- Premier stratigraphy. Pursuant to the recently announced "Plan of Arrangement", Bravada Gold Corp. will focus on exploring Bravo's extensive Carlin-type gold holdings strategically located within the Battle Mountain/Eureka "Cortez" gold trend in Nevada.
Rob Macdonald (P.Geo.) is the Qualified Person responsible for reviewing the technical results in this release.
On behalf of the Board of Directors
Joseph A. Kizis Jr., Director, President, Bravo Venture Group Inc.
We seek safe harbor.
The TSX Venture Exchange has not reviewed and does not accept responsibility for the adequacy or accuracy of the contents of this news release, which has been prepared by management."
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