ABOUT MIMOSA
Aquarius Platinum’s 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.
BACKGROUND
Aquarius acquired at 50% stake in Mimosa Investments on 1 July 2002. Mimosa Investments is jointly controlled by Aquarius (50%) and Implats (50%). The Wedza IV expansion project was completed during 2007 with the $28.8 million Wedza V expansion project due to be completed in early 2008. This project will take production to 195,000 PGM ounces in concentrate and concentrating plant capacity to 175,000 tons milled a month.
LOCATION AND GEOLOGY
Mimosa is located on the southern portion of the Great Dyke in Zimbabwe. After the Bushveld Complex in South Africa, the Great Dyke is the world’s largest PGM orebody.
MINING AND PROCESSING
 Mining commences at a depth of 60 metres below surface, currently extending to approximately 200 metres. Unlike much of the Great Dyke, Mimosa has a well-defined grade profile with an identifiable reef horizon marker facilitating grade control. The operation fits well into the Aquarius portfolio as it is similar in many ways to the company’s Kroondal Platinum Mine in South Africa. Like Kroondal, the bord and pillar mining method is employed. Stoping widths average around 1.8 metres and simple, mechanised shallow mining is the norm. The concentration process is also similar to Kroondal, and concentrate is transported by road to Implats’ Mineral Processes in Rustenburg in terms of the operation’s offtake agreement with Impala Refining Services (IRS). Underground production was successfully ramped up in line with the planned expansion, with an 8% increase in FY2007. The mining operation is in the process of being fully mechanised with the use of drill rigs.
The erratic supply of power remains a challenge but Mimosa has reached agreement with ZESA, the national power authority, that power to meet the mill’s minimum requirements will be maintained and that advance notice will be given on when load shedding will occur. Negotiations on importing power directly from Mozambique are currently in progress. The Wedza V project will take annual production to 195,000 ounces of platinum. Additional exploratory drilling is to be conducted at North Hill to provide additional information on the delineation of the orebody. Mimosa will continue to investigate ways and means of optimising the performance of the plant (Wedza VI). |
