Mine Overview

Ghana Manganese Company Ltd (GMC) is the only manganese producer and exporter in Ghana.  The company is a privately-owned mining company (Consolidated Minerals Africa Limited -90% and Government of Ghana-10% free carried) that holds a mining concession for manganese over an area of 170 square kilometers in and around Nsuta in the Western Region of Ghana, less than 3% of which has been mined to date.

Nsuta is known for its unique high-grade carbonate ore, which is considered to have one of the highest manganese-to-iron ratio ores in the market (Mn: Fe ~31) and is low in phosphorous, alumina, and other heavy metal impurities, making it well-suited for both alloy and manganese metal production.

As an experienced owner-operator with a strong focus on operational excellence and innovation, the company targets to be at the bottom of the cost curve of global manganese producers. It has 3 existing pits in total (Pits A, B, and C) with operations currently active in Pit C.  

Our Production Process

The method of ore extraction is exclusively open-cast, comprising of drilling, blasting, loading, and hauling.

Dry crushing and classification of the carbonate ore into fines, logs, and lumps; by virtue of primary and secondary crushing and screening, is undertaken at the carbonate crushing plant. These fines or lumps are stockpiled according to grade and size.

The processing plant receives the bulk blasted ore at the crusher ROM pad and with the assistance of Front-End Loader CAT 992K feeds the material into the crusher ROM bin. The 600t/h jaw crusher crushes the bulk material with no chemical and water added to the appropriate size for screening and secondary crushing into the final product of fines, logs, and lumps for stockpiling and shipment. The crushing circuit incorporates an automatic dust suppression system to minimize dust exposure to the environment.

The processed ore is then transported to Takoradi Port by road and/or rail.

In 2019, the total tonnes of manganese ore mined was 5.38M @ 26.9%Mn and overburden stripping of 64.25M tonnes.

Drilling

Sandvik Pantera DP1500i drill rigs are used for drilling blast holes with a hole diameter of 115mm. On average 3,000 meters are drilled daily to meet the current production. The average depth of the holes drilled is10.0m with a pattern size of 3.5m x 3.5m. The pattern size may also vary depending on the geology of the area and the fragmentation required.

A designed drilling plan is marked out on the bench (block) by the survey team to show the drillers where each blast hole must be drilled. The drill plan contains details such as the drill depth, sub drill, rock information, and the position to be drilled (the pattern ID).

Blasting

Blasting is conducted at the GMC mine site almost every day. The type of explosives used is bulk emulsion, initiation, and accessory products. The initiation and accessory products are stored in a licensed explosive magazine on the GMC site and only issued when there is time for drilled holes to be charged and blasted. The bulk emulsion is supplied by a contractor.

Loading

The primary loading and hauling equipment used at GMC is a combination of GMC’s owned diesel-hydraulic backhoe excavator fleets along with 100t and 150t dump trucks. The manganese ore is hauled to the processing plant whilst the waste is hauled to the waste dump

Processing and Haulage

Primary hauling equipment consists of 100 t and 150t Komatsu and CAT haul trucks. All manganese ore is hauled to the primary crusher located at the exit of the pit rim where the ore is stockpiled at a rompad. The waste rocks are transported to the CN dump.

Manganese ore from the rompad stockpile is processed (crushed and screened with no chemical and water addition) and stockpiled into different categories of sizes for transportation by rail and road to Takoradi Port.

 

Shipment

Following processing, the Manganese ore product is stockpiled into different size categories. The final product is transported by rail and road to the GMC Takoradi Port terminal. The manganese ore is then loaded aboard Ocean Going Vessels (OGV’s) exported to its clients.

 

Closure Strategy

To deliver on our commitments, we establish closure plans for all our active mining areas before we begin operations. These plans display the steps to be taken throughout the mine life to deliver an effective and sound end to operations, including rehabilitation of the surrounding area and protection of water resources. These plans are regularly updated, and a proportion of the mine’s annual budget is set aside to make sure all closure obligations are met.

Nsuta Mine Process Flow Chart (Mine - Market)

processes chart