VANCOUVER – After a first feasibility study scared investors with its steep price tag and shaky economics, Guyana Goldfields took its Aurora gold project back to the drawing board.
The result is a new mine plan that costs half as much to build and is expected to generate more than twice as much in returns. Investors applauded the initiative, boosting the company’s share price by 10% in a day.
There is a lot of gold at Aurora, which lies in north-central Guyana, but the project is isolated and much of the gold is deep underground – both factors that make the economics of developing a mine at the site more challenging. The initial feasibility study for the project, released 11 months ago, envisioned an 8,000-t/d operation that started in an open pit but quickly transitioned to a shaft-accessed underground operation. The result was a mine that would have cost US$626 to build while generating a relatively low 12.6% after tax internal rate of return (IRR).
Those numbers sparked a major selloff. Guyana Goldfield’s share price plummeted from $8.40 to $4 in the space of two weeks; over the following two months it continued to fall, bottoming at just $1.67 in mid-May.
The project needed a rework and that is precisely what happened. Guyana Goldfields now plans to get Aurora into operation by first focusing on an open pit operation feeding a 5,000-t/d mill and carbon-in-leach (CIL) process plant.
It should cost US$205 million to get that operation off the ground, a feat the company hopes to achieve by early 2015. Once the open pit mine is generating income, the company will slowly set to work developing a ramp-accessed underground component.
The first underground mine area will start producing ore in 2018, and by the end of its days the mine would reach a depth of 1,037 metres.
From 2018 until 2023 Aurora would operate as a combined open pit and underground mine. To process all that ore, the mill would be expanded to 10,000 t/d capacity. Once the open pits are tapped out in 2023, mill throughput would fall back to 5,300 t/d.
Over its 17-year lifespan, the Aurora mine would produce 3.3 million oz of gold, at an average cash cost of US$527 per oz. The strip ratio would average 4.7 to 1 waste-to-ore and the mill head grade would average 2.7 g/t Au. The CIL facility is expected to recover 94.4% of the gold from Aurora’s fresh rock and 97% of the gold from its saprolite ore.
Using a gold price of US$1,300 per oz, the new plan gives Aurora an after tax net present value of US$800 million. The mine would generate a 38% after tax internal rate of return, a huge improvement from the first plan’s 12.6% IRR.
With an initial capital outlay of only US$205 million, the operation would be expected to pay for itself in 3.4 years. In addition, Guyana Goldfields expects to build and sustain the underground portion of the operation from cash flow. From the start of ramp development and mill expansion in 2015 to mine closure in 2031, the underground component is expected to cost US$352 million.
Aurora’s reserve estimate was also updated to go along with the revised development plan. Proven open pit reserves stand at 2.38 million tonnes grading 3.04 g/t Au. Probable reserves total 37.1 million tonnes averaging 2.72 g/t Au, of which roughly 27 million tonnes are classified as underground reserves.
The study excluded several smaller deposits, as they have not been upgraded to reserve status and therefore cannot be included in a feasibility study. For example, at Rory’s Knoll there is 1.1 million oz of indicated gold and 1.3 million oz of inferred gold in addition to the proven and probable reserves considered in the study. Guyana Goldfields will continue to evaluate these resources in an effort to integrate them into the mine plan.
In the meantime, the company has lots of work ahead to finalize the details at Aurora. Located 170 km west of Georgetown, Aurora will have to be a stand-alone operation. As such, a mine at Aurora will require, among other things, a combination diesel and heavy fuel oil power station with a distribution system and fuel storage facility, an airstrip, a river dike and a tailings storage facility, and accommodations for all mine workers.
Guyana Goldfields has sufficient cash on hand to continue planning the mine, but the company says it will need to access additional funds through debt or equity to finance full project construction.
The company has also significantly revised its management team as it transitions from an explorer to a mine developer. Most significantly, the company found a new president and COO in Marcel DeGuire, a metallurgical engineer with 40 years of experience building and operating mines around the world.
News of the revised Aurora feasibility study boosted Guyana Goldfield’s share price to $4.13, a gain of 37¢. The company has 95 million shares outstanding.
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