VANCOUVER (miningweekly.com) – Canadian junior Goldsource Mines is expanding the known saprolite gold deposit at its flagship Guyana-based Eagle Mountain mine, the company announced on Monday.

The Vancouver-based company is completing geotechnical, metallurgical and cost estimation studies at Eagle Mountain, in support of a forthcoming prefeasibility study to examine the potential for a large-scale openpit, gravity-cyanidation operation at Eagle Mountain.

Highlights among the initial batch of results from the drilling work include hole EMCR17-32, with 19 m grading 3.04 g/t gold from surface; and hole EMCR17-06, intercepting 6.7 m and grading 7.51 g/t gold.

The two main objectives of this drilling are to expand the known near-surface saprolite gold mineralisation and re-categorisation of the current saprolite resources from inferred to indicated categories.

“Attaining these objectives will generate information to support a large-scale, low-strip openpit gravity-cyanidation operation at Eagle Mountain,” president Yannis Tsitos stated in a press release.

Of the 282 drilled holes, the company has received results for 44 core holes and 151 auger holes, with 87 holes still outstanding.

Drilling continues with one core drill and two auger drills, the company advised, expecting to add a second core drill on site in September.

RESOURCE EXPANSION
Further, Goldsource expects to expand the core drilling programme from a planned 75 holes to about 150 holes, to be completed before the end of 2017.

Auger drilling has defined a continuous northeast-southwest mineralised (greater than 0.5 g/t gold) trend, measuring about 600 m by 300 m and 5 m to 15 m thick of saprolite. In the fourth quarter, the company plans to do infill core drilling in this expansion area, to test the depth of saprolite mineralisation.

Including both the 2015 and 2017 drilling programmes, Goldsource has, to date, completed 557 holes (core and auger) for 2 429 m to be added for an upcoming revised resource estimation. The company expects to add a further 200 to 300 core and auger holes in the fall, before completing a revised resource estimation.

Meanwhile, in July, the company completed geotechnical drilling, under Tetra Tech’s supervision, for current and potential tailings storage facilities. Several laboratory tests are in progress, with results pending.

PLANT OPTIMISATION
Goldsource has designed metallurgical (cyanidation) studies and will collect and test representative samples under Tetra Tech’s supervision by September. Testing will include material from the current gravity tailings facility for future reprocessing.

Management is currently collecting and analysing detailed costs on its newly operational wet mining method using the Marok pumping system. Testing is under way to determine the use of the cost-effective wet mining method by transporting slurred mineralised saprolite from the pit to the scrubber, then subsequently to the existing pilot gravity plant.

During the second quarter, Goldsource sporadically operated the plant at a reduced average rate (below 300 t/d), which resulted in a subsequent reduction in on-site costs. The company expects operations to continue at a reduced rate during selected days every month, until the optimum processing parameters run on a consistent basis, to support breakeven to positive cash flow in the country.

Goldsource will also operate the plant to further test the wet mining system for potential large-scale mining, cyclone optimisation, and mining and metallurgical testwork for the prefeasibility study.

Gold recovered during testing from January 1, until about mid-August, totalled 68.28 oz, resulting in revenue of C$90 915, net of royalties.

The company’s TSX-V-listed stock tumbled a year ago, after it halved its 2016 guidance, citing weather-related issues, a delay in the shipment of a 40 t truck to site and low-grade ore, while the plant suffered under-plan recoveries. 

The stock is still down some 67% year-on-year at C$0.14 a share, despite gaining more than 17% on Monday.