The Merensky and UG2 Reefs are separated by a sequence of mostly anorthositic and noritic layered units of some 140m to 160m in combined thickness. Both the Merensky and UG2 Reefs are present but only the UG2 is currently exploited. However, no Merensky Reef is present on Tweefontein and the UG2 Reef only occurs on a small portion of this farm. The UG2 Reef outcrops in the Klein Dwarsrivier valley over a north-south strike of 7.5km and dips to the west at 7° to 10°. Due to the extreme topography, the Merensky Reef outcrops further up the mountain slope. The topography also means that the UG2 occurs at approximately 1 650m below surface on the southwestern boundary. The geological succession is broadly similar to other areas of the eastern limb of the Bushveld Complex. An exception is the presence of the Steelpoortpark granite in the southwestern part of the project, which is unique to this area. Three distinct reef types have been defi ned for the UG2 Reef, namely the ‘normal’ reef with a thick main chromitite layer; a ‘split’ reef characterised by an internal pyroxenite/norite lens within the main chromitite layer; and a ‘multiple split’ reef with numerous pyroxenite/norite lenses occurring within the main chromitite layer. The multiple split reef predominates in the southern portion of the mining area. The Merensky Reef is a pyroxenite layer with a chromitite stringer close to the hangingwall contact and also at the basal contact. Mineralisation is primarily associated with the upper and lower chromitite stringers. The graphical illustration of the profi les is shown on the next page. The geological structure of the area is dominated by the regional north-northeast to southsouthwest trending Kalkfontein fault, which has an apparent vertical displacement of 1 200m down throw to the west. A series of sub-parallel faults occur to the south-east adjacent to the Kalkfontein fault, which affect both the Merensky and UG2 Reefs.These faults exhibit variable apparent vertical displacements of between 20m and 110m.

The UG2 orebody is accessed via two decline shaft systems situated 3km apart, namely the Main Decline and the North Decline. Reef production is through a fully mechanised bord and pillar stoping method. A mining section consists of 6m, 8m and 10m bords, with pillar sizes increasing with depth below surface. The pillars are 6m x 6m to 12m x 12m in size. The bords are mined mainly on strike. A 3D geological model with layer grades and widths per stratigraphic unit is used in the mine planning. The mine scheduling of the two declines is done in Datamine Studio 5D Planner™. The schedule is evaluated against the grade and thickness block model. The three distinct reef types including normal-, split reef and multiple split reef facies, impact signifi cantly on the mine plan. Dilution calculations are based on the specifi c reef type. Hangingwall and footwall overbreak, percentage off-reef, ore remaining (mining losses), geological losses (potholes, faults, dykes and replacement pegmatoid) and a shaft call factor are applied to the planned areas to generate the tonnage and grade profiles.

Two Rivers has a concentrator plant on site where initial processing is undertaken. It comprises a standard MF2 design as generally used in the industry. Concentrate is transported by road to Impala Mineral Processes in Rustenburg where further processing takes place in terms of an agreement with Impala.

At the Two Rivers Platinum Mine, which is managed by ARM, material from the UG2 Reef is milled and processed to recover the PGMs at the mine’s MF2 PGM concentrator. The chromite recovery plant then reprocesses the UG2 tailings generated by the concentrator to recover the chromite. The chromite recovery plant was commissioned in 2013 and is owned and operated by Two Rivers, which also has an offtake agreement with Chrome Traders whereby all of the concentrate produced is purchased on a free carrier basis from Two Rivers. Currently some 215kt per annum of chromite is produced at a Cr2O3 grade of 40.1% and a silica content of less than 3.9%, with the remainder being pumped to ........