Tag Archives: Greenland

AEX Gold has high ore sorting hopes following TOMRA Nalunaq tests

Greenland-focused AEX Gold may have found an effective way to distinguish between high-grade gold-containing quartz veins and host amphibolite at its Nalunaq gold project after testing with a TOMRA ore sorting machine produced positive results.

A 500 kg bulk sample of mineralised Main Vein (MV) material, collected from the historical underground workings at Nalunaq, was used for a preliminary performance test at TOMRA’s test facility in Wedel, Germany, with the performance test report confirming that Nalunaq’s mineralised material is “highly amenable” to ore sorting technology, according to AEX Gold.

Laser sorting technology showed favourable results in the preliminary performance test, with total gold recovery ranging between 90.2% and 99.4% and with mass rejections of waste ranging from 58-62% of the incoming feed stream, the company said.

While a second test, planned for 2021, will focus on optimising the detection parameters to increase confidence in gold recovery, AEX already believes ore sorting technology, once optimised, could offer a cost-effective processing solution to supplement the company’s existing plans.

Nalunaq is a past-producing underground mine located in south Greenland. Having produced around 350,000 oz of gold between 2004 and 2009, it has demonstrated a low-cost production potential from past operations, the company says.

Redevelopment plans include developing a mining camp and ancillary facilities to establish a regional hub; carrying out 2,000 m of underground drifts into mineralisation with long hole stoping, operated by a contractor; locating a 300 t/d crushing, milling and gravity recovery plant (65-70% Au recovery) outside of the mine to provide operating scalability and store tailings for future re-processing; refurbishing an existing, permitted leaching plant, located underground, to increase gold recoveries to 95% once free cash flow positive; and adopting new technologies to improve recovery, reduce dilution, and minimise processing costs.

Eldur Olafsson, CEO of AEX, said: “Ore sorting has the potential to be a cost-effective solution for processing Nalunaq’s mineralised material. We are pleased to continue progressing on the development of the Nalunaq project by involving industrial cutting-edge technologies in our development strategies.”

Gold at Nalunaq is mineralised in a MV, which averages 0.7 m in width and exhibits a typical ‘nugget effect’. Past mining operators have used a combination of selective resue mining and conventional long hole stoping, which resulted in an average true mining width of 1.2 m, according to the company.

“Therefore, the mined material includes a significant quantity of amphibolite host rock (devoid of gold and considered as dilution),” the company said. “It is anticipated that ore sorting could be effective at Nalunaq due to the contrast in density and colour between the high-grade gold-containing quartz veins (white) and host amphibolite (dark grey).”

Ironbark Zinc signs up Byrnecut for Citronen underground contract mining

Greenland-focused Ironbark Zinc has signed a memorandum of understanding with Byrnecut Offshore Pty that could see the contractor carry out mining, model underground mine costs and provide the fleet for the Citronen zinc-lead project.

The contract has been signed as Ironbark carries out work on removing key items from the project’s capital cost estimates. A definitive feasibility study last year pegged this at $514 million.

Ironbark said the Byrnecut agreement provides it with “extensive international experience in underground hard-rock mechanised mining”.

It said the companies would work towards a more detailed cost based commercial agreement operating under agreed margins through each project stage, and will also encompass agreed performance margins. As part of the agreement, Byrnecut is also expected to hold the debt and security of the equipment for the underground mining fleet.

Ironbark is in discussions with other groups for the remaining disciplines, or to support the project, that have the potential to collectively and significantly assist with the overall project financing.

The $514 million project envisages a production rate of 3.3 million tonnes per year with up to 200,000 t/y of zinc metal produced over a mine life of 14 years.

Located in northern Greenland, Byrnecut’s first-hand knowledge of the skills necessary to overcome remote location logistics, language barriers and upskilling the national workforce will prove key to development and operating success.

Ironbark Managing Director Jonathan Downes said: “Byrnecut has the capacity to provide Ironbark with an immediate ‘bolt-on’ underground mining expertise that will assist Ironbark as we move from financing to active mining.”