Higher Grade Gold Resource At The Wolfshag Zone
VANCOUVER, - B2Gold Corp. reported a significantly higher grade updated gold mineral resource estimate for the Wolfshag zone located directly adjacent to the east and northeast of the Company's new open pit Otjikoto Mine in Namibia.
The updated inferred mineral resource contains 675,000 ounces of gold within 2.581 million tonnes grading 8.14 grams of gold per tonne (g/t) utilizing a 3 g/t cut-off. This inferred resource is below a pit shell containing an additional 1.035 million tonnes at 2.81 g/t gold (93,000 ounces gold) in the indicated category. Previously released initial inferred resource estimate for the Wolfshag zone was 6.8 million tonnes at 3.2 g/t gold containing 703,000 ounces of gold.
The Wolfshag mineral resource estimate has been prepared using a total of 202 core drill holes (58,050 meters). An additional 31 drill holes (8,207 meters).
Mineral resources are reported within a pit shell based on a 0.5 g/t cut-off grade. Mineral resources located below and down plunge of the shell are reported above at 3.0 g/t gold cut-off grade. The reason that the down plunge resource is still in the inferred category is because the 2014 drill spacing was designed to evaluate the Wolfshag zone from an open pit extraction perspective using a drill spacing of 25 meters by 100 meters. As the majority of the Wolfshag zone is now envisioned to be mined underground, additional drilling will be required to infill the resource to the indicated category (25 meter by 25 meter spacing). Engineering studies are under way to determine which portion of Wolfshag could be mined by open pit and which portion by underground mining.
The Company plans to commence open pit mining at Wolfshag in 2016. The conceptual plan would be to blend higher grade material from Wolfshag with ore from the Otjikoto pit resulting in an increase in annual gold production at Otjikoto and improved project economics. The main Otjikoto open pit deposit is 29.4 million tonnes at a grade of 1.42 g/t gold containing 1.34 million ounces of gold.
In 2015, Otjikoto is expected to produce between 140,000 to 150,000 ounces of gold at a cash operating cost of approximately $500-$525 per ounce and all in sustaining costs of approximately $700 per ounce. Once the planned mill expansion is completed in the third quarter of 2015, increasing the annual throughput at the mill from 2.5 million tonnes of ore per year to approximately 3 million tonnes per year, the Company expects annual gold production to increase to approximately 200,000 ounces in 2016 and 2017. The Company plans to complete an updated mine plan by the end of 2015 which will further evaluate open pit and underground mining at Wolfshag.
The Wolfshag zone remains open down plunge to the southwest. In addition, historic Otjikoto deposit holes such as OT98, with 16.0 meters at 5.07 g/t gold, and OT126, with 3.0 meters at 45.84 g/t gold and 26 meters at 3.74 g/t gold including 7.0 meters at 11.15 g/t gold (true width unknown), indicate the exploration potential of the main Otjikoto high grade shoots below the existing pit. These shoots could possibly be developed underground in conjunction with the Wolfshag resource reported above a cut-off grade of 3.0 g/t gold.
In 2014, the northern portion of the Wolfshag zone (drill sections 8000N to 8850N) was infill drilled to a spacing of 50 meters (along strike) by 25 meters (across strike); the southern portion of the Wolfshag zone (drill sections 7200N to 7900N) was infill drilled to a 100 meter by 25 meter spacing.
As part of the 2014 drill program, nine holes were drilled in the Wolfshag pit shell and a fence of six holes was completed south of the pit shell for evaluating geotechnical characteristics of the Wolfshag zone in support of future engineering studies. Additionally, detailed metallurgical test work was completed in 2014 on a total of 2.5 tonnes of drill samples from the northern portion of the Wolfshag zone using the Otjikoto feasibility study optimized comminution, gravity and leach conditions. These conditions were used as the design basis for the Otjikoto process plant circuit. Gold recoveries for the master and variability composites ranged from 94.9% to 97.8% with overall master composite recoveries of 97.2% (scaled to process plant). In addition, all but one Wolfshag maximum comminution test results are less than the design parameters used for sizing the Otjikoto crusher and grinding mills and the maximum abrasion index of 0.24 g/t is much less (softer ore) than the design abrasion index of 0.47 g/t based on the Otjikoto feasibility testing.