Pan African prepares to exploit a world-class orebody at Royal Sheba, while extending the life of BTRP
Pan African’s focus on exploring the down-dip extensions of the gold orebodies at our Barberton Mines is proving to be the right decision. Drilling results are showing that there are potential high-grade extensions to the orebodies at Fairview, Royal Sheba and Consort mines, and the orebodies remain open at depth.
As it invests in modern geological analysis software to interpret historic data, Pan African is helping to sustain the local economy by increasing the life of its operations around Barberton, a small town where there are few other opportunities for work and advancement. These discoveries will enable us to assist with further community development projects, including upskilling of the local communities.
World-class orebody
Preliminary results at the Royal Sheba project indicate there is a world-class orebody below current workings that, if it were in any Northern American jurisdiction, would justify a separate company listing to invest in the mining operation. We estimate there is an 18-year life of mine here, based on a steady-state production rate of 25 000 t/year, using modern mechanised mining equipment.
At Sheba Mine, we are currently mining the Thomas and Verster orebodies. Previous mining at Sheba only took place in the high-grade sections, which has left a million ounces of lower grade ore in the ground at Royal Sheba. While the grade here is lower than in the rest of Barberton Mines, by employing smart mining techniques, including mine mechanisation, and upgrading our existing processing capacity, we are confident that we can extract it profitably.
Recent exploration drilling at Sheba Mine to locate extensions to the main orebody has intersected several high-grade sections of the reef, with channel widths of between 0.76 and 1.05 metres, grading in excess of 100 g/t of gold. In the 260 Cross fracture and the Northern limb, there is visible free gold (which refers to gold not bound up with other minerals).
We recently started to mine the down-dip mineral resource of the Zwartkoppie (ZK) orebody on 37 level and have drilled ten diamond holes to explore the body between 37 and 38 level. This showed an estimated 3 000 t at 5.2 g/t, and it has enabled us to upgrade some of the ZK orebody to the Measured and Indicated Resources category.
We also drilled two diamond holes into the shallow mineral resources in the Northern limb at Sheba Mine, at 22 level. Another eight diamond holes will be drilled into this orebody in the 2022/23 financial year.
The average grade of the first 5 000 tonnes of bulk sample ore from Royal Sheba was estimated at 0.7 g/t from the grade model, although sampling in the plant has yielded a better-than-expected head grade of 0.94 g/t and a gold recovery of 87%. The strike extent, which we have confirmed from surface, is over 850 metres.
Smart mining unlocking new opportunities
Royal Sheba could be described as an “underground open pit mine”. Such low grades and high tonnages are normally mined from surface in other areas, but this is not possible at Barberton because of heritage sites and nature reserves adjacent to the deposit. However, the deposit is accessible from existing workings as the 23 level haulage in the Sheba Mine ZK shaft is only 180 metres from the expected mineralisation. The width of the orebody lends itself to mechanised mining, which reduces the required labour component and keep down our production costs.
While we are projecting a production rate of 25 000 t/month, this is based on using the milling capacity at the Barberton Tailings Retreatment Plant (BTRP). However, we could increase production to 40 000 t/month by using the Consort and Sheba plants. Having this capacity already in place enhances the economics of the extension project.
Project Dibanisa, which is currently under way, will connect Sheba’s underground infrastructure with Fairview through three ore passes linking Sheba’s 23 level with Fairview’s 38 level haulages. This will optimise costs and efficiencies and enable increased production. We expect the first Sheba ore will be hosted at Fairview in Q3 2023.