TORONTO (miningweekly.com) – Canadian project developer Sunridge Gold, which is developing the Asmara copper/zinc/gold/silver project, in Eritrea, in the Horn of Africa, says fieldwork is proceeding apace on several fronts.

The Asmara project consists of six defined deposits, four of which are the subject of a feasibility study, completed in May 2013, and are in the permitting process.

Sunridge reported on Wednesday that work was currently focused on the two ‘pipeline’ deposits on the Asmara project – the Kodadu volcanogenic-massive-sulphide (VMS) deposit and the Adi Rassi copper/gold deposit – to define new areas of mineralisation and direct additional expansion drilling planned for next year.

Both deposits had inferred mineral resources and were open for expansion.

At Kodadu, Sunridge was busy with channel and trench sampling of the VMS gold oxide and gold shear zones at surface. It was also undertaking detailed geological and structural mapping over the current VMS resource and the gold shear zone that was recently identified to the west.

The team was also conducting geophysical work consisting of an audi-magneto-telluric (AMT) survey to define the massive sulphide at depth below the known VMS gossans exposed at surface, as well as other identified VMS-style targets to the north-east, which both showed high gravity anomalies and strong electromagnetic conductors.

At Adi Rassi, Sunridge was progressing with detailed geological and structural mapping at 1:500 scale and trenching and channel sampling of outcropping mineralisation to the south of the existing resource.

The geological team was also undertaking AMT survey lines to define the VMS-style mineralisation to the west of Adi Rassi.

Meanwhile, Sunridge reported that early development work to build an abstraction weir on the nearby Mai Bela river, which would provide water to the centralised processing facility near the large Emba Derho deposit, was currently proceeding with geotechnical fieldwork involving geotechnical and geological mapping, geotechnical sample collection for laboratory testing and surveying of an access road and staging area.

The Asmara Mining Share Corporation (AMSC) holds the Asmara project, a joint venture (JV) company in which Sunridge has a 60% stake and the Eritrean National Mining Company owns 40%.

The JV was last month formalised and was focused on rapidly pushing the project toward the first phase of production next year.

The Asmara project has demonstrated that mining the four advanced deposits – Emba Derho, Adi Nefas, Gupo Gold and Debarwa –  and processing the ore near the large Emba Derho deposit, was economically robust, with a net present value of $692-million.

Average yearly metal output in the first eight years is estimated at 65-million pounds (29 000 t) of copper, 184-million pounds (83 000 t) of zinc, 42 000 oz of gold and one-million ounces of silver.

Total metal production is estimated at 841-million pounds (381 000 t) of copper, 1.874-billion pounds (850 000 t) of zinc, 436 000 oz of gold and 11-million ounces of silver.

The project has a life-of-mine of 15.3 years. The feasibility study had indicated that full production at Asmara could be achieved by 2018.