Mr. Darin Wagner reports
BALMORAL REPORTS POSITIVE METALLURGICAL RESULTS FROM INITIAL TESTING OF H3 NI-SULPHIDE ZONE AT GRASSET, QUEBEC
Balmoral Resources Ltd. has released the results of initial metallurgical testing conducted on drill core collected from the company's wholly owned H3 nickel-copper-platinum-group-element zone located on the Grasset project in Quebec. Initial testing of samples from two representative areas of the H3 zone produced excellent nickel, copper and palladium recoveries. Locked-cycle flotation tests performed using a simple and conventional flow sheet produced bulk nickel concentrates characterized by good nickel, copper and palladium grades. Based on the initial test work, cobalt, platinum and gold also appear to have potential to provide payable credits in the concentrate.
Initial testing also indicates that the tailings produced from the recovery process would likely not be acid generating, with pH values in the reducing range at 8.7 to 8.8. Metallurgical testing was performed on behalf of the company by Blue Coast Research Ltd. of Parksville, B.C.
"We could not have asked for much better results from this initial phase of metallurgical testing of the H3 zone," said Darin Wagner, president and chief executive officer of Balmoral. "The reported nickel, copper and palladium recoveries rank in the upper quartile for producing and development-stage nickel assets. On top of that, the concentrates produced exhibit good nickel grades with potential for valuable copper, cobalt and precious metal credits and no significant contaminants. Blue Coast has suggested a number of potential paths to further optimize recoveries and concentrate grades as we move forward, but this is a great start."
Metallurgical testing
Head assays and mineralogy
Metallurgical testing was performed on two master composites (MC-1 and MC-2), with average nickel head grades of 1.87 per cent and 1.29 per cent nickel, respectively (see the table). The two samples were selected as being representative of the two principal alteration types within the current outline of the H3 zone. Both master composites display similar mineralogy with sulphides being composed of pentlandite, chalcopyrite, pyrrhotite and pyrite. Electron microprobe analysis indicates that between 94 per cent and 96 per cent of the nickel in the master composites is deported to pentlandite. This high deportment to pentlandite is consistent with the company's observations and the high nickel tenor of the nickel sulphides within the zone.
MASTER COMPOSITE HEAD ASSAYS
Ni Cu Fe S Co Pt Pd Au Ag
Sample % % % % % g/t g/t g/t g/t
MC-1 1.87 0.25 11.11 4.44 0.04 0.38 0.97 0.42 0.92
MC-2 1.29 0.15 9.38 3.10 0.03 0.26 0.66 0.05 0.44
In addition to the two master composites, 12 additional composites were collected and characterized by chemical assays and QEMSCAN automated mineralogical analysis. Over all, the 12 samples showed similar mineralogical characteristics to the two master composites. Four of the 12 exhibit moderate serpentine alteration similar to MC-1, with the other eight exhibiting lower levels of serpentine alteration, similar to MC-2.
Grindability
Grinding tests indicate the H3 sulphide zone exhibits moderate hardness, which should present no significant issues during milling. The Bond rod mill work index was recorded at 12.9 kilowatt-hours per tonne, with the Bond ball mill work index at 11.4 kilowatt-hours per tonne. These values are toward the lower end of average values reported by currently producing nickel operations. MC-2 required approximately half the time to reach a grind of 80 per cent passing 100 microns against MC-1 as a result of the lower percentage of serpentine in MC-2. This suggests some variability in hardness within the zone, and additional grinding tests have been recommended by Blue Coast to better understand this variation.
Flotation -- locked-cycle test results
Flotation test work indicated that a simple and conventional rougher and three-stage cleaner flow sheet, in conjunction with a primary grind of p80 equals 65 microns, achieved the best combination of nickel recoveries and nickel concentrate grades. Results from locked-cycle testing of MC-1 and MC-2, based on these parameters, are shown in the tables. The results were consistent between the two composites, with slightly higher recoveries and concentrate grades yielded by MC-2. These higher recoveries are likely a result of the slightly coarser pentlandite grain size in MC-2, which resulted in improved primary liberation of pentlandite.
SUMMARY OF LOCKED CYCLE TESTS FOR NI, CU AND FE
Assays (%) Recovery (%)
Composite Test ID Ni Cu Fe Ni Cu Fe
MC-1 LCT-2 13.4 1.97 27.4 86.0 93.5 30.1
MC-2 LCT-1 13.8 1.79 29.6 87.3 94.4 25.9
Concentrates grading between 13.4 per cent and 13.8 per cent nickel were produced with nickel recoveries ranging between 86.0 per cent and 87.3 per cent. Copper recovery to concentrate was very high, averaging 94 per cent. Iron to MgO ratios were 5.9:1 and 6.9:1, respectively, for MC-1 and MC-2, representing MgO grades of 3.2 per cent and 3.9 per cent for the two master composites. Minor element scans of the final concentrates did not detect the presence of any significant quantities of penalty elements.
The final locked-cycle test concentrates were assayed for gold and platinum group elements, with the results summarized in the table. Flotation conditions were not specifically optimized for precious metal recoveries as part of this initial testing program. Gold and PGE recoveries were based on a limited data set of feed and concentrate assays, coupled with mass recoveries from the lock-cycle tests, and thus are estimates only and should not be considered as robust as the base metal projections. Rhodium, osmium and iridium assays remain pending.
GOLD AND PGE CONTENT IN THE LOCKED CYCLE CONCENTRATE
Assays Recovery (%)
Composite test ID Au g/t Pt g/t Pd g/t Ag g/t Co Au Pt Pd Ag Co
MC-1 LCT-2 1.88 1.10 7.17 5.00 0.34 54 35 89 89 83
MC-2 LCT-1 0.27 1.56 8.78 6.80 0.29 42 49 N/A* 93 84
* Inconsistencies in palladium assays meant that palladium recovery could
not be adequately determined for MC-2.
Rougher and cleaner flotation tests indicate that the most significant drivers of metallurgical performance are:
- Addition of soda ash and CMC (both standard reagents) for talc depression;
- Primary grinds of approximately p80 passing 65 microns;
- Sufficient cleaner flotation residence time to recover slower-floating pentlandite.
Recommendations for further work
Based on the success of the initial phase of metallurgical testing, Blue Coast has recommended the following additional tests in order to better characterize the metallurgical characteristics of the H3 zone and optimize recoveries and concentrate grades:
- Variability hardness testing to determine the range of hardness within the zone;
- A further evaluation of the conditions that could increase the final concentrate grade by further depressing pyrite and pyrrhotite during flotation;
- Further evaluation of the cleaner circuit to optimize reagent addition and increase talc depression, which could potentially enhance concentrate grades and recoveries;
- Conduct additional flotation testing to determine the range of flotation responses and generate head grade/recovery relationships including additional precious metal testing.
Quality control
The technical information disclosed herein was prepared under the supervision of qualified persons Chris Martin (CEng) and Andrew Kelly (PEng) of Blue Coast Research. Mr. Martin and Mr. Kelly have supervised the metallurgical work reported on and have reviewed and approved the technical disclosure contained in this news release with respect to such work. Darin Wagner (PGeo), president and chief executive officer 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.
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