The mining newspaper for Alaska and Canada's North
The mining newspaper for Alaska and Canada's North
North of 60 Mining News - September 13, 2024
2023 drilling significantly increased the size and grade of the resource within the Dolphin-Cleary deposit at Golden Summit.
Freegold Ventures Ltd. Sept. 10 reported that the Dolphin-Cleary deposit at its Golden Summit project about 25 road-miles north of Fairbanks, Alaska, now hosts 23.8 million ounces of open-pit mineable gold in all resource categories, plus 1.1 million oz of underground mineable gold. While this deposit is already world-class in size, there is substantial evidence that the gold mineralization extends nearly a mile to the west.
The new upgraded and expanded resource for Dolphin-Cleary incorporates the results from the 2023 drill program at Golden Summit and two holes drilled early this year. The resources outlined within the deposit are divided into three groups – open-pit mineable oxide resources, open-pit mineable primary resources, and deeper under-pit resources.
Here is the resource calculation by group:
• Oxide (at a 0.15 grams per metric ton cutoff grade): 59.41 million metric tons of indicated resource averaging 0.49 g/t (937,000 oz) gold; plus 3.25 million metric tons of inferred resources averaging 0.45 g/t (47,000 oz) gold.
• Primary (0.5 g/t cutoff): 346.3 million metric tons of indicated resource averaging 1.08 g/t (12.05 million oz) gold; plus 308.31 million metric tons of inferred resource averaging 1.04 g/t (10.31 million oz) gold.
• Under-pit (0.75 g/t cutoff): 2.87 million metric tons of indicated resource averaging 1.29 g/t (119,000 oz) gold; plus 22.9 million metric tons of inferred resource averaging 1.34 g/t (986,000 oz) gold.
This marks an 8% increase in the ounces of gold and a 9% increase in the grade of the primary indicated resource, when compared to the 2023 resource calculation, and a 45% increase in the ounces of gold and a 23% increase in the grade of the primary inferred resource.
While climbing gold prices added an extra boost to the resource, the gains were offset by more conservative assumptions regarding gold recovery.
The current resource calculation is based on a three-year trailing average gold price of $1,973/oz, which is roughly 10% higher than the $1,792/oz gold price used for the 2023 resource estimate. The new resource, however, assumes that only 72% of the gold will be recovered, which is 20% lower than the 90% recovery rate used last year.
Achieving the higher recovery rate in the 2023 resource calculation required pretreating the ore with high-pressure oxidation to recover refractory gold. Recent metallurgical testing, however, indicates that a significant portion of the mineralization in the Dolphin-Cleary deposit is non-refractory and can be processed without the extra costs associated with oxidation.
Although the recovery is projected to be lower without oxidation, the overall operating and capital cost savings are anticipated to more than compensate for the reduction, as well as substantially simplify project development and operations.
Freegold believes the 72% rate is conservative based on the 77% average recovery rate achieved during testing with standard gravity and carbon-in-leach recovery methods. This is roughly in line with mill recovery rates at Kinross Gold Corp.'s Fort Knox Mine adjacent to Golden Summit, which have averaged just over 78% over the past year.
Material collected from four large diameter holes drilled within the Dolphin-Cleary deposit this year will undergo a comprehensive suite of metallurgical tests to assess various processing methods to improve recoveries and further reduce the project's risks.
Freegold's 2024 drill program is focused on expansion of the already world-class resource at Golden Summit by testing two corridors extending roughly 1,500 meters (0.9 miles) west and southwest of the currently outlined Dolphin-Cleary deposit. For context, the east-west extent of the current resource footprint is 1,500 meters.
In addition to extending the resource west of Willow Creek, this year's program will include infill drilling focused on improving the ore quality and outlining a smaller, higher-grade starter pit within the deposit as the project moves towards pre-feasibility.
With nature already carrying out the oxidation process, higher recoveries can be expected for the nearly 1 million oz of gold contained within the oxide resource lying at the top of the deposit.
Trade-off studies will be conducted to optimize the overall economics and balance improved recovery rates with capital and operating costs as the project progresses toward PFS and feasibility studies.
Over his more than 16 years of covering mining and mineral exploration, Shane has become renowned for his ability to report on the sector in a way that is technically sound enough to inform industry insiders while being easy to understand by a wider audience.
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