Name of the Project
Prieska zinc/copper project.

Location
The project is located 270 km south-west of Kimberley, in the Northern Cape, South Africa.

Client
Orion Minerals.

Project Description
The Prieska zinc/copper deposit has been recorded as one of the world’s top 30 volcanogenic massive sulphide deposits.

The mine was operated from 1971 to 1991, after which it was closed and the site rehabilitated.

Initial metallurgical testwork at the proposed project has yielded positive results, demonstrating Prieska’s potential to produce high-quality marketable zinc and copper concentrates.

The results confirm that the remaining Prieska mineralisation, intersected to date, also responds well to metal concentration using froth flotation and recoveries, which might match or exceed historical performance.

Optimised rougher flotation conditions to produce differentiated copper and zinc concentrates from the deep sulphide target have also been determined, as have preliminary rougher conditions to produce a bulk copper and zinc concentrate from the shallow 105 Level target (openpit). Historical rougher flotation conditions have been improved through varying reagent dosages and supplementary modern reagents. The resultant rougher products are well suited to upgrading in cleaner circuits to produce saleable products. Cleaner flotation testwork is continuing. Orion MD and CEO Errol Smart has indicated that the project will likely comprise an openpit and underground operation, with the openpit to produce ore while the underground operations are dewatered and re-established.

The baseline project that Orion is evaluating envisages the mine producing about 100 000 t/m. This rate would translate into 12 000 t/y to 15 000 t/y of copper concentrate and 20 000 t/y to 25 000 t/y of zinc concentrate – consistent with the mine’s historical output.

Potential Job Creation
Not stated.

Net Present Value/Internal Rate of Return
None stated.

Value
Not stated.

Duration
The project could start production by 2020. The project timeline envisages the completion of a Joint Ore Reserves Committee- (Jorc-) compliant resource estimate by the first quarter of 2018, the lodging of a mining right application in the second quarter, feasibility study results by the fourth quarter and the start of construction of the plant in mid-2019. The proposed underground operation will likely start production by 2022.

Latest Developments
Orion Minerals has announced further encouraging results from drilling at the Prieska zinc/copper project.

Drill hole OCOD087_D2, drilled on the south-west margin of the NW trough target, has intersected 14 m of mineralised massive sulphide and contained mixed, fine- to coarse-grained cumulates, as well as veinlets of metal sulphide minerals, typically of composition pyrite, pyrrhotite, sphalerite and chalcopyrite, with a combined content of more than 40%.

This intersection confirms that the thick massive sulphide mineralisation included in the inferred resource reported on February 8, is open down-dip and to the south-west, and emphasises potential to increase the current mineral resource in the NW trough target area.

In addition, Orion has completed 56 intersections from 24 mother holes into the deep sulphide target.

The intersections have been achieved at vertical depths from 974 m up to 1 193 m and have required 9 462 m of percussion precollar and 33 713 m of diamond drilling.

All completed intersections are now reported, while five holes are in progress testing up-dip extensions, the company has said.

However, the company has explained that drilling is currently focused on the up-dip area in the NW Hinge target, which is more challenging to drill, and slower drilling progress is expected.

Permitting of the SE target extension is expected to be completed in the coming weeks so that drilling can continue to test the strike extent of the deep sulphide target.

Key Contracts and Suppliers
None stated.

On Budget and on Time?
Not stated.

Contact Details for Project Information
Orion Minerals, +61 3 8080 7170, fax +61 3 8080 7174 or email info@orionminerals.com.au.