Overview
Exploration review

Given the Group’s present constrained economic situation, exploration focus is being limited to current operations and one continuing offshore project where positive results warranted follow-up.

Bushveld Complex in South Africa

Exploration on and around the Impala mining area focused on infill drilling at 20 Shaft and at least one borehole was drilled on each of the RBR JV prospecting areas, comprising portions of the farms Doornspruit and Roodekraalspruit, and the farms Diepkuil and Klipgatkop. Drilling in support of ongoing mining operations was conducted at 11C Shaft, 14 Decline Shaft and 16 Shaft. Elsewhere limited drilling was conducted at Afplats on the Kareepoort/Wolvekraal extension area. At the Tamboti Project two boreholes were drilled on Portions 4 and 5 of Kalkfontein and two boreholes on Tweefontein in conjunction with Two Rivers and in fulfilment of prospecting right obligations.

Great Dyke in Zimbabwe

At Zimplats exploration drilling at the proposed Portal 5 boxcut and decline position was completed during the 2015 financial year and the focus on the interpretation of geotechnical and geological data around Portal 5, Bimha and Mupfuti Mine footprint continued throughout the year. The extent and influence of the Mutambara shear and Manzamnyama fault were the prime objective of the 3D structural mapping and logging exercises that were undertaken following the failure of mine pillars at Bimha Mine. Regional structures were mapped in greater detail using various methods, including interpretation of existing aeromagnetic surveys and additional wireline down-hole geophysical applications were employed. Improved understanding of the ground has been achieved to date and it is anticipated that further studies will be conducted in the coming year in order to improve the prediction of reef and ground conditions ahead of mining.

The assay results for surface holes drilled during the Portal 7 – 10 drilling campaign of 2012 were received and incorporated into new block models and this resulted in the upgrading of some portions of the mineral resource from an “inferred” category to the “indicated” category.

At Mimosa exploration work involved the geological studies based on the drilling that was carried out during the previous year on the western limb of the South Hill ore body to investigate perceived low grades in the area as well as drilling for fault investigation on the northern section of the mine close to the ore body limit. Similarly the results of the earlier exploration drilling at the Far South Hill ore body were used to re-assess the mineral resource estimates.

Offshore projects

Implats’ main geographic focus offshore was Canada where it is exploring PGM mineralisation in the Sunday Lake intrusion 25 kilometres north of Thunder Bay, Ontario. The programme, a joint venture owned 75% by Implats and 25% by Transition Metals Corp., was initiated last year and discovered PGM mineralisation with high Pt:Pd ratios, typically >1:1. The Sunday Lake PGM-Cu-Ni property covers a 3.5km diameter circular reversely-polarised magnetic anomaly associated with a large buried Proterozoic-aged mafic-ultramafic intrusion related to the Midcontinental Rift of North America, a feature known to host several significant nickel-copper-PGM deposits.

Exploration commencing last year culminated in exploration drilling that intersected significant PGM mineralisation in the northern margin of the intrusion and in dykes extending to the north. Results reported last year included 20.2 metres grading 3.22 g/t combined PGMs, a 15 metre interval containing 2.84g/t PGMs and a 5.0 metre interval averaging 5.0g/t PGMs. A small additional drill programme in the latest year confirmed the presence of an extensive PGM mineralised horizon within the northern part of the intrusion. Two holes encountered 10.9m of 2.3g/t PGMs including 3.29g/t PGMs over 4.9m and 17.8m of 1.95g/t PGMs including 3.30g/t PGMs over 7.0m. The third hole failed to intersect the target horizon before it exited the intrusion. To date, only the northern portion of the intrusive complex has been tested by drilling. A more extensive drill programme to explore the untested southern part of the intrusion is envisaged for the 2016 financial year.

Elsewhere Implats continues to monitor exploration developments worldwide and review numerous exploration and potential mining opportunities.