JOHANNESBURG (miningweekly.com) – Zimplats, a unit of South Africa’s Impala Platinum, would complete a preliminary study on the second phase of the Ngezi expansion project by the first quarter of 2010, the company said on Wednesday.

The second phase expansion would consist of a two-million ton a year underground mine, a concentrator module of the same capacity, and related infrastructure.

The Ngezi concentrator was officially opened during October, but only reached full production by September.

Zimplats stated in its quarterly report that the development of the Portal four underground mine was on schedule to reach full production by May 2011, and was still expected to be completed within the approved budget.

For the quarter ended September, ore mined increased by 18% when compared with the previous quarter, owing to the ramping up of underground production. The ore stock pile at the end of September was 838 000 t.

With the ramp up of the Ngezi concentrator, tons milled were 61% above the previous quarter. The four elements (4E) platinum group metals (PGM) mill grade was lower than the previous quarter, owing to grade dilution arising from the milling of lower grade open-pit ore from the stock pile.

4E recovery, which was recorded at around 80,6%, was 4% below the previous quarter, owing to a reduction in mass pull, in line with smelter capacity constraints and the ongoing process optimisation at the Ngezi concentrator.

Zimplats stated that 4E metal production and sales were 51% and 47% higher than the previous quarter, respectively, reflecting the higher milled tons following the commissioning of the Ngezi concentrator.

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