RBPlat is located on the Western Limb of the BIC, one of the three main portions or limbs which all comprise similarities in their formation, economic potential and type of commodity. The Bushveld Complex formed approximately 2.04 billion years ago, comprising three main suites, namely the Rooiberg Group, Lebowa Granite Suite and the Rustenburg Layered Suite. The Rustenburg Layered Suite comprises four main zones (the upper, main, critical and lower zones) with each zone characterized by signature igneous intrusive layering, known as stratigraphy. The critical zone hosts the platinum group element (PGE) bearing reef (the economically important layer) types of the Merensky reef and the Upper Group 2 reef (UG2). RBPlat’s operations mines Merensky and UG2 reefs.

The western extremity of the Maseve ore body subcrops 190m below surface. The northern boundry is the operational Wesizwe Platinum’s mining right area, and the remainder of the ore body borders RBPlat operations.

Proximity of the basement (and possibly its paleotopography) to the Merensky and UG2, by and large influenced the geometry and succession of the local stratigraphy, which primarily resulted from local basement upliftment. Upliftment caused the folded or rolling nature of the stratigraphic geometries which are preserved as anticlines and synclines. The frequency of the rolling towards the west becomes narrower with steeper dips resulting in some of the stratigraphic units not developed. The implication of the folding and or rolling nature of the stratigraphy results in opposite dip directions (westerly and easterly) with wide ranges of dip-regimes that exist. The aforementioned is contrary to traditional narrow tabular Merensky and UG2 stratigraphy with recognized local changes in the planarity of the ore bodies, which are mostly related to the different fancies types.

The Merensky and UG2 reefs are both sulphide enriched with the Merensky reef being the main economic horizon mined at RBPlat. The PGMs (platinum (Pt), palladium (Pd), rhodium (RH), osmium (Os), ruthenium (Ru)) as well as gold (Au) are found mostly within the sulphide minerals and include varieties of copper (Cu) and nickel (Ni) as accompanying base metals. The reef horizons dip towards the north-eastern direction between 50 and 120 . The steeper dips are in the north-eastern part of the Styldrift, with the shallower dips presents in the center and western of the farm.

The average depth of the Merensky reef is 505 metres below surface (mbs), with RBPlat having the advantage of being the Merensky reef dominant relatively mine. The newly operational Styldrift I shaft ore from a 50 dipping Merensky reef horizon at an average depth of 712mbs.

The Merensky reef across the RBPlat operational area comprises six different geological facies types, from west to east, namely the Abutment, Terrace, Central, Normal, Normal Thick and Main reef facies. Merensky reef facies delineation of the Maseve ore body ties in with the regional RBPl at Merensky reef facies; Abutment facies (divided into shallow Abutment, deep Abutment and transition to Terrace facies) on the most western side and Terrace facies further east towards the Styldrift I shaft area. Each facies type exhibits unique geological, geochemical and mineralization characteristics which has a fundamental role in planning the optimized mining method. The predominant facies type at Maseve Mine is the Abutment facies, which is commonly associated with intrusions.

The vertical separation between the Merensky and the UG2 reefs varies from an average 80m at BRPM to 50m around the Styldrift I shaft area and decreases to an estimated minimum of 25m in the far north-eastern region of the mining area (Styldrift II). This is due the overall thinning of the critical zone of the Bushveld Complex, in a north-eastern direction towards the Pilanesberg Complex. The UG2 ore body has been classified and subdivided into three main facies types based on the occurrence of the position of the leader UG2 chromitite bands in the hangingwall of the dominant mineralized main chromitite band. These facies variations are encountered on apparent dip in a north- eastern direction, ranging from the Central high facies, Leader facies and General facies, from the shallowest to deepest portions of the mining area. The predominant facies types are the Leader and General facies, which account for 85% of the total ore body.

Due to the nature of the Merensky reef ore body, the Styldrift I shaft is designed to optimally extract the reef by two different mining methods. These consist of bord and pillar mining by means of trackless mechanised equipment for the flat dipping, stable, wide mineralised areas and conventional scattered breast mining for the more undulating Terrace reef facies towards the western, shallower portions of the ore body. Although the Terrace reef facies is planned to be mined by hybrid mining methods, RBPlat continually re-evaluates the optimisation of the mining methods to achieve maximum, efficient long-term extraction.

Styldrift I shaft is designed to hoist 230ktpm of reef and 20kt of waste at steady state.

The underground working areas are accessed via a vertical twin shaft system, which comprises a Main shaft and Services shaft. The shaft system hoisting capacity is designed to allow for the possible future mining of the UG2 reef. The Main shaft, with a diameter 10.5m, sunk to a depth of 758mbs, is used for person, material and rock hoisting. It also serves as an air intake shaft. The Services shaft, with a diameter of 6.5m, is sunk to a depth of 723mbs. The Services shaft is used for services, a second egress and an air intake shaft.

The ore handling and ore breaking philosophy at Styldrift comprises the use of trackless mechanised vehicles and mechanical conveyance installations. Trackless mechanised vehicles include load haul dumpers (LHD), dump trucks, roof bolter, drill rigs and utility vehicles. The ore handling on 600 level utilises LHD’s to load the broken ore on the face, which is then transported to the side tip facility feeding a strike conveyor belt installed from the start of the section extending up to the current workings. Strike conveyors feed an ore pass system linked to 642 Level where the ore from 600 Level feeds onto a different conveyor belt used to convey the ore to the shaft silos. Ore is drawn from the silos on 708 Level to feed the skips in the shaft enabling the hoisting the ore
to surface. Through an overland conveyor belt system, ore is then conveyed to the concentrator for processing.

The current minimum mining cut considers the mechanical bolting equipment. Additional overbreak of the 186cm resource cut, reef in hangingwall (RIH) and reef in footwall (RIF) content are discounted in the total content delivered. All other excavation tonnages are added to the stope cut, which includes planned on-reef re-development, based on the replacement rate and layout including tip excavations and primary on-reef development.

The BRPM concentrator, was designed to receive Merensky ore from BRPM’s two decline shafts and is able to treat 10% of UG2. The original design capacity of 200ktpm, was upgraded to 250ktpm to accommodate production from Styldrift.

The concentrator can be described as a robust maintenance intensive environment which produces 2.7 tonnes of saleable product from every 100 tonnes of ore processed

The plant operates on a 24 hours, 365 days a year basis and follows a traditional Mill- Float, Mill-Float (MF2) process which includes a conventional three stage crushing process prior to milling and flotation. The flotation processes produce a platinum rich PGM concentrate which is collected and sold as a final product for further processing and refining.