Key Features
| Location: |
Wedza Geological Complex on the southern portion of the Great Dyke in Zimbabwe |
| Comprises: |
Shallow underground mine accessed by decline shaft and a surface concentrator plant |
| Management: |
Managed by Mimosa Investments Limited, which is jointly controlled by Aquarius and Impala Platinum Holdings Limited (Implats) on a 50:50 basis |
| Production: |
Total production of 180,023 PGM ounces in FY2009
Production attributable to Aquarius was 90,011 ounces (19% of group attributable production) |
| Life of Mine: |
20 years plus |
| Refining: |
Concentrate offtake agreement with Centametal AG of Switzerland. In terms of this contract, concentrate produced by Mimosa is delivered to Impala Refining Services in South Africa for processing and refining |
| Number of employees: |
1,931 – including contractors |
About Mimosa
Aquarius’ 50% interest in Mimosa provides the company with a prime, long-life asset and a foothold on the Great Dyke in Zimbabwe, one of the world’s largest known primary PGM reserves.
Mining currently extends to approximately 200
metres. Mimosa has a well-defined grade profile with an identifiable reef horizon market facilitating grade control. The operations fits will into the Aquarius protfolio as it is similar in many ways to the company's Kroondal Mine in South Africa. Like Kroondal, the bord and pillar mining method is employed. Stoping widths average around 2.0 metres and simple, mechanised mining is the norm. Mechanisation of the mining operation, including the use of drill rigs, is complete.
The concentration process is also similar to that at Kroondal, and concentrate is transported by road to Implats’ Mineral Processes in Rustenburg in terms of the operation’s offtake agreement with IRS.
Location and Geology
Mimosa is located on the Wedza sub-chamber on the southern portion of the Great Dyke in Zimbabwe. It is an elongated north-northeast-trending intrusion that is 550km long and between 4km and 11km wide. Economic PGE-mineralisation occurs with the Main Sulphide Zone (MSZ) which is lithologically continuous, generally 10m to 50m from the top of the ultramafic sequence and typically 2m to 3m thick.
Production
Following the challenges of FY2008, Mimosa had a more stable, steady year operationally in FY2009, especially in the second half. In particular, the instability that had been experienced in the power grid was overcome which facilitated operational improvements.
Tonnes mined rose to 2.111Mt, an increase of 11%. Of this 2.1Mt were processed and the balance stockpiled to bring the stockpile at year-end to 236,000 tons, equivalent to one month’s mill feed. The average head grade rose by 1% to 3.60g/t while recoveries fell marginally to 74%. This was due to unsteady processing operations in the first and third quarters of the year due to mill breakdowns. There was however, a significant improvement in recoveries in the last quarter of the financial year. Overall, total PGM production increased by 19% to 180,023 PGM ounces.
The Wedza Phase 5 expansion increased monthly mill processing capacity to 175,000tpm. This was followed by the commissioning of the Wedza Phase 5.5 expansion which further increased processing capacity to 185,000tpm, equivalent to PGM production of approximately 197,000 ounces annually. Conceptualization work for the Wedza Phase 6 expansion project has began. It is anticipated that implementation of this project will result in a significant increase in processing capacity.
The production target for FY2010 is around 197,000 PGM ounces, which is full production capacity. There are no major expansion plans in the short to mid-term period. The current operations will however be optimised from nameplate capacity of 185,000 to 195,000tpm milled ore.
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Mimosa Mine
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Mimosa Mine
The Mineral Resources and Mineral Reserves have been confirmed in accordance with the South African Code for Reporting of Mineral Resources and Mineral Reserves (SAMREC 2007) and its equivalent, the Australian Code for Reporting of Mineral Resources and Ore Reserves (JORC 2004).
