Name and Location
Blue Vein gold project, Australia.

Client
Convergent Minerals.

Project Description
A scoping study has highlighted strong economics for the underground development of the Blue Vein deposit in the Mt Holland goldfield. Studies have identified primary flotation treatment of the ore, followed by a high-intensity cyanide leach to be the most cost-effective way of processing.

Mining scoped at Blue Vein involves accessing the gold resource through the ramp into the existing opencut mine – a technique known as in-pit decline development. From the pit, a portal and a decline are established with a planned 1:7 decline slope angle. The portal will be developed at a position at least 20 m above the bottom of the pit to ensure a sump is maintained for any water inflow to the pit.

The decline is planned at 5 m x 5.5 m dimensions, with models assuming basic ground support requirements, with standard meshing and bolting of the backs during advancement. Lateral development drives are planned at 3 m x 3.5 m dimensions. The mining is designed to be up-hole benching with levels developed every 15 m.

Initial metallurgical testwork has confirmed that two techniques may be successfully employed to recover gold from Blue Vein. A conventional cyanide carbon-in-pulp (CIP) leach process results in recoveries of up to 96%. A second technique is to form a heavy mineral concentrate before cyanidation. Testwork shows that a flotation concentrate can be readily achieved, with more than 93% of the gold reporting to the concentrate. With the subsequent cyanide leaching of the concentrate, recoveries of gold exceed 98%. The scoping study identified an optimum throughput of 300 000 t/y with an average head grade of 5.64 g/t of gold.

Value
The scoping study estimates the processing plant capital cost at less than $16-million.

Duration
Not stated.

Latest Developments
The scoping studies have demonstrated that, by keeping throughput at 300 000 t/y, an underground operation with an initial 2.5-year mine life provides an excellent opportunity for Convergent to start production and build the operation gradually from profits generated.

While the mining and deeper exploration of Blue Vein is under way, the company expects to drill and develop the Bush Pig, Earl Grey, Darjeeling and other mines within the goldfield. Viable options exist for the company to eventually add a CIP circuit, which will enable the company to mine and treat the substantial oxide resources at each of the pits within Convergent’s mining leases.

Once Convergent’s board has fully considered the results of the scoping study, the company will start feasibility studies, including definitive mine design, reserve estimation and process flowsheets. Drilling will also be undertaken for waste characterisation studies and to confirm the geotechnical integrity of the rocks along the path of the planned decline. This drilling is expected to provide a dual benefit of lifting more of the resource into the measured category of Joint Ore Reserves Committee confidence. A definitive underground mine design will be completed, which will lead to the estimation of a maiden reserve at Blue Vein.

Permitting for mining and processing has started, with initial meetings with the Department of Mines and Energy taking place and the project summary report being prepared.

The company expects to complete this feasibility work at the end of the 2014 March quarter.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
Convergent Minerals, tel +61 2 9956 8750, fax +61 2 9956 8751 or email info@convergentminerals.com.