West Red Lake Gold Mines Ltd. (TSXV: WRLG) (OTCQB: WRLGF) announced positive metallurgical test results from the Rowan Mine Deposit, which is part of the 100% owned Rowan Property located in the prolific Red Lake Gold District of Northwestern Ontario, Canada.
Highlights of Metallurgical Test Results
The Rowan Mine Deposit exhibits an excellent response using conventional metallurgical techniques with a very high percentage of Gravity Recoverable Gold (“GRG”). As expected, the GRG component occurs as coarse gold, which is also seen at Madsen and the satellite deposits Russet, Fork and Wedge (the “Satellites”). The metallurgical test work was completed using the Madsen Mill Flowsheet with the samespecifications and parameters currently in place at the Madsen Mill.
• Test work completed on the Rowan Master Composites (“MCs”) indicates that Rowan vein material can be processed through the Madsen Mill with minor changes to the existing flowsheet.
• The results indicate the MCs tested produce very high gravity recovery with overall gold extraction above 98% after a 48-hour cyanide leach of the gravity tailings.
• Gravity Recoverable Gold (GRG) ranged from 75.8% to 94.9% and the gold was found to be coarse to very coarse.
• At a primary grind of 80% passing (P80) 75 microns, very low cyanide consumptions, below 0.23 kilogram per tonne (“kg/t”), were required to achieve gold extractions above 98%.
Details of Metallurgical Program
The metallurgical test program (the “Program”) was completed by Base Metallurgical Laboratories (“BaseMet”), a leading metallurgical testing and consulting firm based in Kamloops, British Columbia. The test work was completed on four (4) MCsamples representative of Rowan vein zones 101, 102, 103 and 104 (“MC-101”, “MC-102”, “MC-103” and “MC-104”, respectively). The MC samples were created from contiguous intervals of material from 14 NQ-diameter diamond drill holes throughout the Rowan deposit. The metallurgical test program was designed and supervised by Kelly McLeod, P.Eng. (K-Met Consultants, Inc.).
TABLE 1 shows the head grades for the four MCs. Due to the nuggety nature of the gold in the material, MC head grades vary with each test charge – for example, a range of 4.6 to 15.3 g/t Au was measured during the leach tests.
Discussion of the Metallurgical Program Results
The preliminary test work completed on the Rowan MCs indicates the material can be processed through the Madsen Mill with minor changes to the existing flowsheet. The results indicate the MCs tested produced very high gravity recovery with overall gold extraction after a 48-hour cyanide leach of the gravity tailings above 98%. Like Madsen, the leach tests were completed at low cyanide consumptions and successfully achieved the target Cyanide Weak Acid Dissociable (“CNWAD“) in the final tailings of less than 1 ppm using the previously established Madsen conditions for cyanide destruction.
Mineralogy and Comminution
Bulk Mineralogy Analysis (“BMA”) was completed on all four MC samples. As observed at Madsen and the Satellite deposits, the main sulphides present are pyrrhotite followed by pyrite.Sphalerite is also present at Rowan and tends to often bespatially associated with visible gold.
Comminution test work conducted on the MCs yielded the following results:
• The Rowan samples tested were harder than the Madsen and Satellite deposits.
• The Bond Ball Work Index (“Bwi”) for the Rowan MCs ranges from 16.2 to 18.2 kilowatt-hour per tonne (“kWh/t”) – for comparison Madsen ranges from 9.7 to 17.1 kWh/t and averages 14.4 kWh/t.
• The SAG Mill Comminution (“SMC”) test results are outlined in TABLE 3 below.
• Gravity Recoverable Gold (GRG) test work was completed on MC-101, -102 and -103.
• All three MCs have a significant amount of coarse gravity gold.
• MC-101, MC-102 and MC-103 had a GRG of 93.0%, 94.9% and 75.8%, respectively.
• The gravity component is coarse to very coarse as seen in the Madsen and Satellite deposits.
• The leach tests were completed using the Madsen Mill Flowsheet.
• The gold extraction at 24 hours (residence time in the Madsen leach circuit) was above 95%for all four MCs tested with high gravity recovery – for comparison, the Madsen mill averaged 95%.
• The final extractions at 48 hours were above 98% with cyanide consumptions below 0.23 kg/tonne.
• High gravity recoveries to the pan concentrate of over 67% were recorded with the exception of MC-103 which had a recovery of 42.3%. Operational data from the Madsen mill averaged 45% recovery to the pan concentrate.
• Due to the coarse nature of the Rowan gold and slightly slower leach kinetics of MC-102 an additional leach tank will be added to the flowsheet.
• The Madsen detox circuit is designed for 1 hour residence time, 5:1 SO2:CNWAD and 30 mg/L CuSO4.5H2O with a target of less than 5 ppm CNWAD.
• The cyanide destruction test work completed on the MC’s indicates the Rowan material can achieve a final tailings CNWAD of less than 1 ppm Au following the Madsen design parameters and flowsheet.
Additional Test Work and Opportunities
Additional metallurgical test work at Rowan will include PFS-level studies to confirm extraction with varying head grades, as well as running the flowsheet on a number of variability samples from throughout the Rowan deposit.
The Rowan Mine Target consists of more than seven sub-parallel, near-vertical, east-west trending veins that are currently defined over a strike length of approximately 1.1 km– mineralization remains open along strike and at depth. The orientation of the veins at the Rowan Mine tend to follow the direction of D2 deformation, which is oriented in an east-west direction over this part of the property. Individual mineralized vein zones usually average 1.0 to 1.5m in thickness, with an overall thickness of the Rowan vein corridor at around 115m. Gold mineralization is typically localized within quartz-carbonate veins hosted within and along the ‘footwall’ margin of a porphyritic felsic intrusive, with increased grades often associated with the presence of visible gold and base metal sulphides (e.g. galena, sphalerite). High-grade dilation zones or ‘ore chutes’ along the Rowan vein trend have been recognized as important controls for localizing thicker and higher-grade zones of gold mineralization. The position and geometry of these dilation zones is well understood at Rowan.
The drilling completed at the Rowan Mine Target in 2023 has been focused on validating historical data across the Inferred Resource, and also infilling apparent gaps in the analytical data set which was a product of very selective sampling techniques implemented during previous drilling campaigns. Assay results received from the 2023 drilling program continue to confirm our thesis that quartz veining and gold mineralization continue at depth and along strike, with grades consistent with, or higher than those outlined in the current Inferred Mineral Resource which remains open in all directions. For example, the 100 Vein Zone – which is the furthest north vein currently modeled within the overall Rowan vein corridor – was previously interpreted to be a lower grade portion of the block model. Recent drilling has confirmed that higher grades are present within the 100 Vein Zone below 150m elevation, suggesting that gold grades are increasing at depth within this zone which is a trend that has been observed elsewhere in the Red Lake district. Drilling at the Rowan Mine Target area will continue with an emphasis on infill and expansion of the existing high-grade mineral resources.
West Red Lake Gold is a market awareness client of Capital 10X.
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