SWARTKOPFONTEIN MANGANESE PROJECT
INVESTMENT: US$3 million
Manganese Minerals (Pty) Ltd
The Swartkopfontein Manganese Project is a mining operation by Manganese Minerals (Pty) Ltd and located on two tenements, the farms Zwartkopfontein 7 KO and Secheli’s Oude Stad 6 KO which are made up of a total of nine manganese ore blocks. The deposit was originally acquired by Rand Mines Ltd that carried out comprehensive exploration in 1976/77 on the two farms, and resource drilling has indicated that the in-situ ore has an average grading of 34.85% in a zone averaging 3.8m in thickness. Bulk sampling and petrography studies conducted on the property has confirmed the geology and manganese resources originally delineated by the Rand Mines exploration. Independent mineralogical and metallurgical tests by the University of Natal and Mintek showed that the manganese ores can be upgraded to a medium-to-high grade Mn product.
Location
The project is located 80km northwest of Zeerust town, in the district of Lehurutse, North West Province, on the border of South Africa with Botswana.
Fig. 1: Locality map
Ore Deposit Blocks
A total of nine discrete ore deposit blocks have been identified, extending over a total strike length distance of some 15km. Six ore blocks are found on the farm Zwartkopfontein and three on the adjacent farm Secheli’s Oude Stad.
Fig. 2: Plan showing the ore blocks
Fig. 3: Geologists examining the ore
Ore Characteristics
The ore is ferruginous and siliceous in character consisting of manganese mineral association: institute-pyrolusite-psilomelane. Three types of manganese mineralization can be recognised on the property and they grade into each other, namely, “spotty”, “patchy”, “ferruginous” and “porous” ores. These deposits, as opposed to the large metallurgical grade deposits of the Northern Cape, consists of manganese dioxide which can be refined to chemical grade manganese.
Fig. 4: Manganese ore from Block 2 Pit 2
Exploration and Drilling
Historical core drilling information on the properties was reviewed to determine the thickness and depth variations on the mineralized horizon. From this information a better understanding of the geological and structural control was discerned. This information was used in planning the RC drilling programme.
Fig. 5: RC Drilling in Pit 2
Fig. 6: RC Drilling sample collection
Fig. 7: Plan showing positions of the drilled boreholes
Fig. 8: Contours showing the varying depth to the top of ore body
Mining Operation
The mine layout plan currently consists of an office complex, plant complex and storage area. The mining operation is currently taking place on Area 2 Pits 2 and 3. Mining is focussing on the shallow dipping manganese outcrop area, and ore is hauled by trucks and transported to the processing plant for washing. The shallow outcrop areas have indicated higher grades as compared to the down dip areas.
A practical and simple mine design would need to be produced in order to ensure maximum exploitation of the manganese resources and consideration of the safety of employees and stakeholders for the down dip areas and strike extensions. The current production is on average 5,000 t/m. The Plant produces tonnages which average at 35% lumpy and 35% fines product with 30% being produced as discard material.
Fig. 9: Aerial view of the mining complex
Processing Plant
Ore is processed on site at a plant designed for low production volume of under 15,000 tons per month. The manganese ore is transported to the processing plant which comprise of a standard crushing and screening process to create a marketable product with a particle sizing of -70mm +0mm. The technology applied is a jaw crusher, a multi-deck screen, and a cone crusher. The final product will have a particle sizing of -70mm to +0 mm and a manganese content of 34% Mn.
The processing plant incorporates conventional multistage crushing plant with grizzly ahead of both the primary and secondary crushers. The ROM is dumped through a 10" grizzly into a coarse ore bin. The ore is discharged by an Apron Feeder to feed the primary Jaw Crusher. This crusher is equipped with a 2½" opening shaking grizzly to remove the undersized material. ROM is pre-screened to minimize the amount of sand going through the processing plant-washing facility.
Fig. 10: Processing plant
Ore Washing uses hydraulic washing and additional mechanical scrubbing to separate the ore from the mud. This is accompanied by screening which entails washing directly on the vibrating screen or sending the ore obtained by the washing machine to the vibrating screen.
Fig. 11: Processing plant water retention section
Technical Team
Manganese Minerals makes use of a qualified and motivated workforce with the experience and expertise to deliver on the project plan. The mine is currently managed by a Technical Team that includes a Mining Engineer and Geologists. The technical team leads the extraction and throughput of product from the mining operation through processing to load-out in a safe and cost-effective manner according to the provisions of the approved business plan.
Fig. 12: Operational Technical Team
Investment Requirements
The Project owners are seeking capital investment into their operation to enable them to upgrade the processing plant to ramp up production from the current 5,000 tonnes per month to a minimum of 20,000 tonnes per month and also to undertake some targeted drilling in Area 1 to supplement production levels.
Investors sought can therefore be in any of the following categories or a combination thereof:
- 1. Lender — for debt
- 2. Equity Investors — for equity, or
- 3. Offtakers — for pre-production investment to secure future product supply
Manganese Minerals is therefore seeking a total investment of ZAR52 million (about US$3 million).
Manganese use in Steelmaking
The most important use of manganese is in the manufacturing of steel. Approximately 90% of the consumption of manganese is to produce manganese ferroalloys, which can remove impurities and improve the physical properties of steel during the process of steel-making. Manganese gives the steel strength and hardness. Without manganese, the steel used to make armor plate, crusher jaws, and impact tools would not be as durable. Its global mining industry is dominated by just a few nations, hence in countries like the US it is considered to be one of the most critical mineral commodities.
Manganese removes oxygen and sulfur when iron ore (an iron and oxygen compound) is converted into iron. It also is an essential alloy that helps convert iron into steel. As an alloy, it decreases the brittleness of steel and imparts strength. The amount of manganese used per ton of steel is rather small, ranging from 6 to 9 kilograms. About 30 percent of that is used during refinement of iron ore, and the remaining 70 percent is used as an alloy in the final steel product.
Other uses of Manganese