Guyana Goldfields Advances Aurora Project

Overlay shows location of ore deposits at Guyana Goldfields’ Aurora gold project in northwest Guyana.
(Photo courtesy of Guyana Goldfields)
Toronto-based Guyana Goldfields reported in late August 2009 completion of a positive, NI 43-101 compliant preliminary assessment of its Aurora gold project in northwest Guyana, along with plans to complete a definitive feasibility study by March 2010. The project is located 170 km west of Georgetown, Guyana’s capital, in an area of low relief and dense rainforest. Rainfall averages 2,500 mm per year. The project can be accessed by barges during highwater levels, six months of the year.

The proposed mine plan calls for production of 250,000 oz/y of gold over a 16- year mine life, first from open-pit and then from underground operations. The open-pit tonnage would total 17.9 million mt at an average grade of 2.8 g/mt, while the underground tonnage would total 18.1 million mt at an average grade of 4.5 g/mt.

The Aurora ore is mainly non-refractory sulphides, with a small portion of oxides (saprolite) near surface. The proposed flowsheet calls for SAG and ball-mill grinding, followed by gravity and carbon-in-pulp (CIP) circuits. Mill throughput is proposed at 8,000 mt/d.

Capital expenditures for the Aurora project are projected at $262 million for pre-production development of the openpit and surface operations, $21 million for surface equipment, $147 for underground development, $10 million for underground equipment, and $80 million for sustaining capital, including cost of closure. Operating costs are estimated at $364/oz.

The preliminary assessment assumes an open-pit production fleet of 15 Caterpillar 777 trucks, four Cat 992 loaders, and 6.5- in. down-the-hole drills. Underground access would be via a 4.5-m wide by 4.5- m high ramp at a negative gradient of 17% and a 5.8-m-dia, concrete-lined shaft to a depth of 1,400 m. The shaft would be equipped with a double-drum hoist and 12- mt skips with slung cages on both sides. Underground mining would be by sub-level open stoping, with typical stope dimensions of 20 m long, by 20 m wide, by 30 m high. Underground production equipment would include hydraulic two-boom jumbos, 5-m3 capacity LHDs, and 28-mt and 50-mt capacity trucks.

The Aurora project timeline includes two years for construction and development (2010-2012), start of open-pit operations in 2012, open-pit life of nine years, first underground production in 2015, and underground operations from 2015 to 2028.

Guyana Goldfields holds a 100% interest in the Aurora project, subject to a 5% royalty payable to and determined at the discretion of the Guyana Geology and Mines Commission. Guyana Goldfields submitted a preliminary environmental impact assessment for the project to the Guyanese Environmental Protection Agency in June 2009, and the company reports that the permitting process is proceeding well.

As featured in Womp 2009 Vol 08 -