The Tshipi Mine is located on the southern extremity of the Kalahari Manganese Fields (“KMF”), which covers an area of approximately 23,000 hectares. The KMF is known to contain approximately 80% of the world’s in-situ manganese resources. It is important to note that the Tshipi orebody is contiguous with and is the direct extension of South32’s (formerly BHP) Mamatwan operation that has been producing manganese for over 50 years. The KMF is dominated by the Hotazel geological formation comprising three sedimentary manganese layers interbedded with banded iron formations. Of the three sedimentary manganese layers, the lower manganese deposit is the best developed and laterally continuous. The middle and upper manganese orebodies act as stratigraphic markers rather than potential mining targets given the relatively low manganese content contained in these layers.

The Hotazel Formation is underlain by basaltic lava of the Ongeluk Formation (Transvaal Supergroup) and directly overlain by dolomite of the Mooidraai Formation (Transvaal Supergroup).

The Transvaal Supergroup is overlain unconformably by the Olifantshoek Supergroup, which consists of arenaceous sediments, typically interbedded shale, quartzite and lavas overlain by coarser quartzite and shale. The different formations at the Tshipi Borwa Mine include the Mapedi and Lucknow units. The whole Supergroup has been deformed into a succession with an east-verging dip.

The Olifantshoek Supergroup is overlain by Dwyka Formation, which forms the basal part of the Karoo Supergroup. At the Tshipi Borwa Mine this consists of tillite (diamictite), which is covered by sands, claystone and calcrete of the Kalahari Group (SLR, 2017c).

Tshipi is exploiting the manganese from the banded iron stones of the Hotazel Formation. The ore is contained within a 30 to 45 m thick mineralised zone which occurs along the entire Tshipi Borwa Mine and is made up of three manganese rich zones; the Upper Manganese Ore Body (UMO), the Middle Manganese Ore Body (MMO) and the Lower Manganese Ore Body (LMO).

The lower manganese orebody (“LMO”) consists of banded, very fine-grained braunite-kutnahorite lutite, containing concretionary ovoids, laminae and lenticeles of Mn-calcite with which hausmanite is commonly associated. The LMO is 37.5 m thick on average, dips toward the north- west at an average of 7º, and is subdivided based on geological features and metal content, into six sub-zones termed “N, C, M, Z, Y, X”. The grouped N, C, and M zones average 19.5 m thickness, with 37.5% Mn grade and Mn/Fe ratio of 8.5. This constitutes the average grade ore mined by Tshipi. The overlying Z, Y and X zones contain 31.0% Mn and have a Mn/Fe ratio of 5. This constitutes Tshipi’s lowgrade ore that is either mined and blended with average grade ore, or sold as standalone low-grade product.

The poorly mineralised MMO is approximately 1 m thick and not economically viable.

The UMO is 10 cm to 15 cm thick and comprises moderate deposits of manganese.

The Kalahari Manganese Field, which is 35km long and 15km wide, is the largest Mnbearing geological formation in the world. Tshipi Borwa Mine is an open pit Mn mine with an integrated ore processing plant. Tshipi Borwa Mine is located on the southwestern outer rim of the Kalahari Manganese Field, hence the ore resources are shallower and more amenable to open pit mining.

Tshipi’s strategy is to mine and process the lower 15m of the mineralised zone, commonly known as the bottom cut, as it bears higher-grade ores. A portion of the upper 15m mineralised zone, referred to as the top cut, is planned to be stockpiled for possible use later.

Operations comprise conventional truck and shovel open pit mining methods. The mining of the open pit commenced in the south-east of the mining right area and is progressing in a northerly direction. The depth of the manganese seam at the start of mining was approximately 70 m below the surface and the deepest point will be approximately 330 m below surface.

Once the topsoil and some of the waste rock has been removed by dozing, the waste rock is drilled and blasted in benches until the economic ore horizon is exposed. Similarly drill and blast methods are used to break the ore with careful attention being paid to avoiding contamination of the ore with waste. Blasting occurs only a few times a week i.e. not daily and only in daylight hours. Blasting does not take place on weekends under normal circumstances. Access to the open pit is by means of engineered ramps from either the high wall, low wall or end wall of the pit. In the future, access to the underground workings will be by means of adits or portals excavated off the high wall on the ore-body horizon i.e. on the floor of the open pit.

Broken waste rock is loaded into mining dump-trucks by excavator and then hauled either to the worked out area of the pit or onto the surface WRDs where it is tipped and dozed into final position.

Broken ore is also loaded by excavator into mining dump-trucks and then hauled either directly to the ROM pad – adjacent to the mine tip and crusher or to various grade stockpile areas. The ROM is then transferred into the primary crusher from where it is conveyed to the crushed ore stockpile. From the crushed ore stockpile it is transferred to the secondary crushing and screening plant.The extended ROM stockpile area is only utilised when the designated ROM pad is unable to accommodate for the ROM tonnages at that time. In addition to this, a temporary ROM stockpile area near the ROM pad is utilised in the event that there is a shortfall in capacity at the ROM stockpile. Low grade ore that cannot be sent for crushing and screening is stockpiled at one of the product stockpile areas (No. 1 and No. 2). Low grade ore is sent off-site for sale via truck and/or train.

Tshipi Borwa Mine is an open pit Mn mine with an integrated ore processing plant. Once exposed, the Mn ores are drilled, blasted and loaded onto trucks and hauled to the main ROM stockpile.

The ROM stockpile feeds the processing plant which is designed to treat 3.3-3.6 mtonnes p.a. of Mn ores. These products are stockpiled before loading through a stateof-the-art load-out station onto railway trains or road trucks. Inland transportation of Mn products from the mine site is carried out by rail, and complemented by a combination of road and rail solutions to increase logistics capacity. Tshipi’s products are then exported through: a) the Port Elizabeth bulk terminal; b) the Port Elizabeth multi purpose terminal; or c) the Saldanha multi-purpose terminal.

Primary crushing and screening
ROM is delivered to the primary crushing and screening plant with mining dump trucks. The primary (jaw) crusher reduces the size of the run-of-mine ore to fractions manageable by the secondary crusher i.e.

Crushed ROM ore is conveyed to the crushed ore stockpile, adjacent to the secondary crushing and screening plant.

Dust suppression by means of water sprays is installed at the tip, the primary crusher, screens and conveyor transfer points.

Secondary crushing and screening
The secondary crushing and screening plant is used to size the ore according to product specifications. Crushed ROM ore is first screened and the >75mm ore reports to a cone crusher before reporting to a the <75mm stockpile. The <75mm ore is then reclaimed by conveyor and screened to produce two stockpiles; a 75mmm X 6mm lumpy product and a <6mm fines product. Dust allaying by water sprays at the crusher, screens and conveyor transfer points is done continuously while the plant is in operation. The water is either retained as surface moisture on the ore or evaporates, there is minimal if any run-off water.

Front end loaders and haul trucks are used to transfer the ore to the product stockpiles adjacent to the rail load-out facility. As trains arrive at the mine product ore is reclaimed and put into the wagons via a load-out silo. Road trucks are loaded with front-end-loaders form the same product stockpiles.

Proposed
Thickener and tailings dam (not constructed or commissioned at this time)
Secondary screening fines waste (<1 mm) material is sent to the thickener plant via conveyor. Water removed from the secondary screening fines waste during the thickener process is re-used within the mining system as process water for dust suppression at the primary and secondary screening plants. The fines waste processed at the thickener is disposed as tailings.

Tertiary crushing and screening (not constructed or commissioned at this time)
The tertiary crushing and screening section (-40+6 mm material) is used to prepare the ore for sinter plant feed. High grade product is stockpiled at the tertiary product stockpile prior to being sent to the sinter plant. Manganese that is below the required grade from the tertiary crushing and screening plant is stockpiled at a low grade stockpile prior to being sent to the Dense Medium Separator (DMS) for further processing. Any fines material (-1 mm) produced at the tertiary crushing and screening plant are sent to the thickener for disposal to the tailings dam.

Sintering (not constructed or commissioned at this time)
In the sinter plant, ore is sintered by the application of heat, to agglomerate it and to increase the manganese content (by burning off the carbonaceous material). Raw materials are mixed with the manganese ore in a rotating mixing pan prior to agglomeration in a rotary drum. The agglomerated material is fed into the sinter furnace on a steel belt. The sinter furnace is a multi- compartment oven that is ignited with gas or heavy fuel oil. The front compartments are used for drying, ignition and sintering. The back compartments are for cooling. Gas emissions are scrubbed in cascade scrubbers to remove most of the particulates and pollutants. The dirty scrubber water is re-cycled in the thickener plant. Dust emissions are captured in bag filters and recycled into the sinter feed. The final product is stockpiled on the product stockpile prior to being loaded onto trains for sale to third parties.

Dense medium separation (not constructed or commissioned at this time)
Prior to the sintering stage, manganese ore that is below the saleable manganese grade is beneficiated using DMS, effectively upgrading the ore. Using density differential between manganese and waste; the material is sent to the sinter feed stockpile prior to being sent to the sinter plant while the waste is disposed onto the temporary discard dump.