Tag Archives: AngloGold Ashanti

Master Drilling’s Mobile Tunnel Borer heads to Anglo’s Mogalakwena mine

Master Drilling is readying its Mobile Tunnel Borer (MTB) technology for a contract at Anglo American Platinum’s Mogalakwena mine in South Africa.

The company, which revealed the news during its interim results presentation, said on-boarding for this project deployment was underway, with the start of “decline excavation” due by the end of the year.

Anglo American Platinum said in its own interim results recently that it was working on feasibility studies on the future of Mogalakwena, with completion of these studies expected at the end of 2021. Decisions on the pathway forward are expected shortly after this, however, one of the current key milestones at the asset includes progressing an underground exploration decline.

Master Drilling Executive Director, Koos Jordaan, said during the presentation that the contract with Anglo American Platinum is for a “turnkey operation” with Master Drilling providing capabilities in terms of construction, logistics and project management, in addition to its normal excavation services.

The MTB is a modular horizontal cutting machine equipped with full-face cutter head with disc cutters adapted from traditional tunnel boring machines. Unlike these traditional machines, it is designed to work both on inclines and declines, with the ability to navigate around corners and construct 5.5 m diameter decline access tunnels.

One MTB unit was previously scheduled to carry out a 1.4 km project at Northam Platinum’s Eland platinum group metals operation in South Africa, however this was cancelled in March 2020 due to the pandemic. This deployment followed testing of an MTB unit in soft rock at a quarry just outside of Rome, Italy, in 2018.

Alongside news of this latest MTB deployment, Master Drilling said in its results that it was studying the potential to deploy two of these MTB units in tandem for twin-decline access as part of the technology’s second-generation developments.

“We can already see the benefit of utilising two of these machines to do a twin-decline access to an orebody,” Jordaan said.

Looking to vertical developments, Master Drilling reported that it had received shareholder funding approval from the Industrial Development Corporation for the latest work on its Shaft Boring System (SBS), designed to sink 4.5 m diameter shafts in hard rock down to 1,500 m depths.

IM witnessed the main cutting mechanism of what was previously billed as being a 45-m long, 450-t machine at the back end of 2019.

The company has since said it will introduce a “smaller scope system” as part of its introduction to the industry.

While busy on the latest slimmed down design of the SBS, Master Drilling has signed a letter of intent with a prospective South Africa project that could see a machine start sinking activities in the first half of 2022, Jordaan said.

Outside of these developments, Master Drilling reported on several contract awards across the globe, including a three-year raiseboring extension with AngloGold Ashanti in Brazil, a joint venture agreement with Besalco Construction to work on Codelco’s Chuquicamata copper mine, an executed contract with Glencore’s Raglan mine in Canada, an agreement with Zimplats in Zimbabwe and a “long-term contract” on the Khoemacau copper-silver project in Botswana.

Macmahon books A$600m of work with Newcrest, AngloGold and Vale

Macmahon Holdings has bolstered its order book with a number of contract extensions involving the Tropicana and Telfer gold operations, in Western Australia, and the Hu’u copper-gold project, in Indonesia.

At the Tropicana mine, a joint venture between AngloGold Ashanti Australia Ltd (70% and operator) and Regis Resources Ltd (30%), Macmahon has been providing mining services since open-pit mining started in July 2012 under a life of mine alliance contract.

The additional work for Macmahon follows the completion of a detailed final cutback study of the Havana pit and subsequent confirmation of the optimal method to mine the deeper ore in the Havana ore body. Macmahon has now been provided with the scheduling detail for the cutback, which will add 155 Mt to the material to be mined from 2024.

The final cutback of Havana will extend the open-pit mine life by four years, from 2023 to 2027, and is expected to generate additional revenue of approximately A$470 million ($340 million), it said.

Macmahon has also extended its life of mine contract with Newcrest for the Telfer mine.

On August 12, Newcrest announced it will proceed with the West Dome Stage 5 cutback at Telfer. This new scope of work is expected to generate revenue of circa A$138 million and will extend Macmahon’s work on site to September 2024. This new work has been negotiated on updated rates, which are forecast to achieve the company’s internal financial hurdles, Macmahon explained.

In Indonesia, Macmahon has received a letter of award to construct an 11 km access road at the Hu’u copper gold exploration project on Sumbawa island. This work is valued at approximately A$18 million and is a further step in the company’s strategy to increase its revenue from mining support services.

Subject to finalisation of contract documentation, the project is forecast to commence in September 2021 and employ approximately 150 people. The Hu’u project is 80% controlled by Vale SA. Vale has previously said the project could produce more than 250,000 t of copper and more than 200,000 oz of gold.

Macmahon CEO and Managing Director, Michael Finnegan, said: “We are pleased to have secured this additional work which adds approximately A$600 million to our order book. A key highlight is the extension of our long-term alliance contract at Tropicana, which has been a cornerstone of our surface mining business in Western Australia for many years and has recently expanded into underground mining.”

Vale, Glencore, Newcrest and others join BluVein’s next gen trolley charging project

Seven major mining companies have financially backed BluVein and its “next generation trolley-charging technology” for heavy mining vehicles, with the industry collaboration project now moving forward with final system development and construction of a technology demonstration pilot site in Brisbane, Australia.

BluVein can now refer to Northern Star Resources, Newcrest Mining, Vale, Glencore, Agnico Eagle, AngloGold Ashanti and OZ Minerals as project partners.

Some additional mining companies still in the process of joining the BluVein project will be announced as they officially come on board, BluVein said, while four major mining vehicle manufacturers have signed agreements to support BluVein controls and hardware integration into their vehicles.

BluVein, a joint venture between EVIAS and Australia-based Olitek, is intent on laying the groundwork for multiple OEMs and mining companies to play in the mine electrification space without the need to employ battery swapping or acquire larger, heavier batteries customised to cope with the current requirements placed on the heaviest diesel-powered machinery operating in the mining sector.

It is doing this through adapting charging technology originally developed by Sweden-based EVIAS for electrified public highways. The application of this technology in mining could see operations employ smaller, lighter battery-electric vehicles that are connected to the mine site grid via its ingress protection-rated slotted Rail™ system. This system effectively eliminates all exposed high voltage conductors, providing significantly improved safety and ensures compliance with mine electrical regulations, according to BluVein. This is complemented with its Hammer™ technology and a sophisticated power distribution unit to effectively power electric motors and charge a vehicle’s on-board batteries.

BluVein has been specifically designed for harsh mining environments and is completely agnostic to vehicle manufacturer. This standardisation is crucial, BluVein says, as it allows a mixed fleet of mining vehicle to use the same rail infrastructure.

While underground mining looks like the most immediate application, BluVein says the technology also has applications in open-pit mining and quarrying.

It is this technology to be trialled in a demonstration pilot in a simulated underground environment. BluVein says it plans on starting the trial install early works towards the end of this year for a mid- to late-2022 trial period.

The BluVein project will be managed by the Canada Mining Innovation Council (CMIC).

AMS to continue servicing AngloGold’s Iduapriem with help of MAXMASS

AMAX, a joint venture between Perenti Global’s surface mining business in Africa, African Mining Services (AMS), and Ghana-based mining services company MAXMASS Ltd, has been awarded a new circa-A$470 million ($346 million), five-year contract at AngloGold Ashanti’s Iduapriem gold mine in the Western Region of Ghana.

Perenti’s work in hand will increase by circa-A$280 million over the term of the contract, which is expected to commence immediately.

The new contract is structured as a 60:40 joint venture agreement between AMS and MAXMASS and represents AMS’ significant and ongoing commitment to developing and expanding the capacity and capability of local partners, Perenti explained.

Mark Norwell, Managing Director and CEO of Perenti, said the continued transformation of AMS, including the winning of quality projects underpinned by robust financial and commercial disciplines, remains a key strategic initiative in Perenti’s 2025 Group Strategy.

“We’re delighted to be extending our relationship with our long-standing client, AngloGold Ashanti,” Norwell said. “AMS has a reputation for delivering excellence while generating enduring value and certainty for stakeholders and the award of this new contract at a site where AMS has previously operated for AngloGold Ashanti provides further support for that reputation.”

Perenti Mining Chief Executive Officer, Paul Muller, said AMS had a long history of delivering operational excellence and value to clients, having provided mining services in Ghana for 30 years.

“We have provided surface mining services at the Iduapriem gold mine since 2012, establishing a successful partnership with AngloGold Ashanti,” he said. “We look forward to continuing to strengthen this partnership and also welcome the opportunity to work with our newest joint venture partner, MAXMASS.

“We have a strong commitment to support and build local capability to generate social and economic value for the regions in which we operate. Under this contract, and through the AMAX joint venture, we expect to continue to support the many local businesses that have become important suppliers and contractors to our operations under previous contracts. The joint venture also expects to employ more than 475 Ghanaians with approximately 40% of the workforce employed from the surrounding local communities and the remaining 60% from other regions within Ghana.”

Iduapriem is an open-pit mine with two circuits each comprising two-stage milling – a gravity circuit and a carbon-in-leach (CIL) plant. The gravity circuit recovers about 30% of the gold and the remainder is recovered by the 418,000 t/mth capacity CIL plant, according to AngloGold.

Perenti’s AUMS wins two-year extension at AngloGold’s Geita operation

Perenti Global’s African Underground Mining Services (AUMS) has secured a new two-year contract to continue operations at AngloGold Ashanti’s Geita Mine in Tanzania.

The two-year agreement will take effect immediately and comes with a value of $186 million (100% share).

As part of the new contract, Perenti will transfer 20% of equity in AUMS Tanzania to a newly created mining support services company called BG Umoja Services Limited. BG Umoja is an 80:20 joint venture between Perenti group entities and local drilling services and mining supply company, Geofields Tanzania Limited, which will supply mining support services to the Geita mine.

The establishment of the BG Umoja JV demonstrates Perenti’s ongoing commitment to support and build local capability, generating enduring social and economic value for the regions in which the company operates, Perenti said.

The Geita Complex is located within the Lake Victoria Goldfields of the Mwanza Region, about 120 km from Mwanza and 4 km west of the town of Geita. The Geita Mine was originally an open-pit operation, however, transitioned to an underground operation in 2016. Since this transition, AUMS has worked collaboratively with AngloGold Ashanti to provide a full suite of integrated underground mining services for the mine.

AUMS Tanzania, supported by Geofields, will continue to provide AngloGold Ashanti with underground mining services while facilitating the development of improved underground mining technical capability within the broader Tanzanian workforce.

Mark Norwell, Managing Director and CEO of Perenti, said: “We are very pleased to be continuing our strong, long-term working relationship with AngloGold Ashanti at their flagship Geita Mine.

“Furthermore, this contract extension includes the addition of Geita Hill, a new underground development within the Geita Complex, which will see a steady increase in our scope of works and revenue run rate as the development ramps up from a single heading decline into multiple work areas and then into production later in 2021. This contract extension is expected to generate an improved earnings contribution for Perenti over the contract term.”

Perenti’s Mining Chief Executive Officer, Paul Muller, said Perenti first started operating in Tanzania in the late 1990s and the award of the contract extension at the Geita mine provided it with an opportunity to continue to partner with, and support numerous local businesses, suppliers and contractors.

“We look forward to expanding on these relationships as we seek to create enduring value and certainty for all of our stakeholders,” he said.

Capital receives underground drilling boost at AngloGold’s Geita mine

Mining service company Capital has been awarded two new three-year contracts at AngloGold Ashanti’s Geita gold mine in Tanzania.

Included in these contracts is the continuation of surface delineation and open-pit grade control drilling services, plus underground grade control and delineation drilling, with an expanded scope for underground drilling activities.

The award, Capital says, is subject to final contract execution and relevant government approvals. Both contracts are due to commence on April 1 and are anticipated to generate revenues of $65 million over the contract term.

The underground contract will use nine rigs, including five from the existing fleet together with an additional four new rigs, which have been secured and are currently in transit to the site. The surface delineation contract will use the existing fleet of five rigs.

Capital has been providing drilling services at Geita since 2006.

Jamie Boyton, Executive Chairman, said: “The awarding of the contracts at the Geita Gold Mine maintains our long-standing relationship with AngloGold Ashanti and is in line with our strategy of focusing on long-term mine site contracts with premier clients, underpinning the sustainability of our business. The contracts, which have been expanded from the previous contracts, reflect the Capital team’s excellent operational performance in safely delivering drilling services at the site since 2006.”

Hyperspectral imaging technology tested at Western Australia gold, iron ore mines

The University of Queensland and research partners Plotlogic Pty Ltd have developed new automated mining technology that, they say, will facilitate automation of the mining process while improving operating efficiency.

The research has shown how artificial intelligence can use scans of the mine face to almost instantly identify valuable minerals and waste rock, allowing each stage of the mining process to be planned more effectively in advance, UQ said.

Professor Ross McAree, Head of School of Mechanical and Mining Engineering from UQ, said the new technology used visible and infrared light to automatically classify materials.

“Each mineral has its own characteristic response to different wavelengths of light, so by scanning the mine face with our system we can map out the minerals present in the rock and their concentration (ore grade) almost instantaneously,” Professor McAree said.

This real-time mapping allows the mining process to be planned out before digging even starts, according to the researchers.

“Beyond this immediate efficiency gain, the enhanced ability to recognise ore grade could also underpin future autonomous mine systems,” Professor McAree said. “Machines equipped with this imaging system would be able to recognise ore grade as they were excavating it. Linked to artificial intelligence, this could allow automated machinery to operate in the mine environment, removing workers from hazardous parts of the mining process.”

Real-time ore grade classification at the mine face could also enhance mine scheduling and improve resource recovery and minimise processing waste, the researchers claim.

The project was supported by the Minerals Research Institute of Western Australia (MRIWA), with MRIWA CEO, Nicole Roocke, saying investment into research like this helped position Australia’s minerals industry at the leading edge of technology development.

“This imaging approach could prove particularly valuable where rapid extraction and consistency of ore grades could provide a competitive advantage to those leading the way,” Roocke said.

The project, which was conducted in 2018-2019, had a total grant value of A$850,850 ($653,322). In addition to MRIWA, UQ and Plotlogic, CITIC Pacific Mining and AngloGold Ashanti were also involved, hosting trials at the Sino iron ore and Tropicana gold mines, in Western Australia, respectively.

It was based off the OreSense® prototype system, developed to meet the needs of the research project, as well as offering a commercial pathway for early industry adoption of the technology.

“The prototype delivers a system capable of acquiring, processing and classifying hyperspectral data in the field and in real time, mapped to terrain and geo-referenced for integration with mine maps,” the project partners said. “In order to be the most general and applicable to all minerals, the hyperspectral imaging capabilities cover the visible to short wave infrared spectrum (400-2,500 nm).

“The surveying capabilities of the system rotate in more than one axis to perform face scans and build a 3D data-cube from two individual line-scanning hyperspectral sensors. The system spatially and spectrally fuses the data cubes from the two sensors to provide a single data-cube for an entire scene. The system also performs on-board corrections and post-processing of the hyperspectral data to support real-time ore grade classification.”

The prototype used on site during the trials consisted of a sensor head with LiDAR and hyperspectral cameras, a pan-tilt unit and a GNSS receiver among other elements (see photo above).

Swift Media wins more business from Western Australia mines

Swift Media Ltd says it has secured two new technology, entertainment and support contracts with Atlas Iron and a contract extension from AngloGold Ashanti, both in Western Australia.

The specialist technology company which delivers entertainment, communications and advertising to remote locations such as mine sites, has booked A$2 million ($1.56 million) in total contract value from its latest pacts, which also includes a contract extension with LNG focused Inpex Operations.

The Atlas Iron contracts at Miralga Creek and Sanjiv Ridge, in Western Australia, will see Swift provide its On Demand communication and entertainment platform and ongoing support for a 36-month term, plus Wi-Fi internet, fibre works, GPON network replacement, and data cabling for the Miralga Creek Village starting in March.

Swift has also extended its AngloGold contract, thought to be at Tropicana, which will see it supply in-room entertainment and ongoing support in 1,042 rooms for 11 months starting February 2021.

Nitrogen tyres and oxygen generators bring safety and sustainability to mines

David Cheeseman*, Chief Engineer of Oxair Gas Systems, believes the mining industry should take on board the latest on-site gas generation technology to help improve safety and reduce its carbon footprint.

The mining industry is becoming a lot more technology-focused, with advancements in autonomous mining technology and automated surface vehicles, as the industry presses ahead to reduce carbon emissions and boost safety in mining.

The International Council on Mining & Metals’ (ICMM) Innovation for Cleaner, Safer Vehicles (ICSV) initiative – a supply chain collaboration with original equipment manufacturers (OEM) – is to be applauded. However, in the meantime, rugged terrain will still be taking its toll on the tyres of mining vehicles, which are the workhorses of the extraction process.

These trucks operate in harsh environments and extremes of temperatures, which is why nitrogen-filled tyres are ideal, because they remain inflated for longer and are more resistant to hot climates and freezing at high altitudes, making them safer for operators and site staff alike. Unlike compressed air, nitrogen is an inert gas that does not react with other materials, so it is resistant to corrosion and, therefore, provides an extra tier of safety where critical applications are involved.

It is imperative that tyres are fully inflated to reduce the risk of critical air leaks and rapid deflation when the vehicles are under pressure. But being at the mercy of the supply chain for bottled nitrogen, especially in extreme locations where conditions are challenging, is costly. Nitrogen can be difficult to transport, not to mention the additional carbon footprint of delivery vehicles and safety risks for staff manually moving cylinders from one place to another, especially with the new threat of contamination posed by the coronavirus pandemic.

However, companies can avoid the hassle of having to outsource their gas from conventional cylinders by switching to an on-tap supply through a nitrogen generator. A nitrogen generator on site is the ideal alternative choice to manhandling canisters for heavy-duty equipment where precise or constant pressure is vital.

Oxair’s nitrogen generators are efficient and compact, making them an ideal solution for mining sites. They offer a continuous flow of gas extracted from the atmosphere and are an environmentally friendlier method of delivery, as they reduce the carbon footprint associated with having

Oxair’s nitrogen generators are efficient and compact, making them an ideal solution for mining sites, David Cheeseman says

cylinders transported from an off-site facility and then the return journey when they are empty.

Nitrogen generators are cheap to run and, once installed, require minimal maintenance. Nitrogen plants are built to last and are operator friendly, making them crucial where tyres need to perform well in a remote location or challenging environment.

As with all high-quality engineering solutions, nitrogen generators can be tailored exactly to suit an individual mine’s requirements. They can be designed for outdoor or covered facilities and, as well as offering low energy consumption, a supplier should be able to provide on-site training to enable local employees to properly calibrate and easily maintain the system once it is operational, as well as full ongoing maintenance support.

Some of the world’s leading gold mining companies are already seeing the benefits of gas on tap at sites rather than taking deliveries of traditional cylinders. Pressure Swing Adsorption (PSA) oxygen equipment supplied by Oxair is helping AngloGold Ashanti extract more of the precious metal from one of its flagship gold mines, potentially extending the life of the open-pit operation in Tanzania.

Two booster processors for increasing oxygen pressure and two oxygen generator tonnage plants to further improve the efficiency of the leaching process are in operation at AngloGold’s Geita Gold Mine, enhancing gold recoveries and protecting the environment by reducing cyanide consumption.

This equipment is helping to increase production and extend the mine’s lifespan beyond 2025, when it was originally set for closure. The state-of-the-art equipment supplied, which includes upgraded control systems, will double the reliable source of pure oxygen for the future activities planned at Geita. It will mean significant efficiencies in carbon in the leach technology method of gold recovery and should help the mine be both economically and environmentally sound for its extended lifespan.

Using oxygen generators significantly improves the gold dissolution process through adding highly purified oxygen at the slurry stage of leaching. Mined rock is usually ground up and turned into a slurry by adding lime, cyanide, oxygen and water before being fed through a carbon bed to extract the gold. Incorporating highly purified oxygen allows cyanide to work more efficiently and, thus, reduces the quantity of cyanide needed in the process.

A PSA tonnage plant takes oxygen directly from the air using on average of only 3 kW of electricity per 100 cu.ft of oxygen produced and transforms it into highly purified oxygen by removing nitrogen entrainments (which are useless to the leaching process).

Using oxygen generators significantly improves the gold dissolution process through adding highly purified oxygen at the slurry stage of leaching

Oxygen tonnage plants are designed for on-site applications requiring large amounts of oxygen, such as mining, with outdoor or covered standard installations – PSA equipment is bringing numerous advantages to the mining industry, as well as eliminating the need for expensive and unreliable deliveries of liquid or cylinder oxygen.

On-site generators provide mines with a turnkey solution for getting a constant, reliable source of high-quality oxygen and nitrogen where it is needed. It is clear that with responsible mining practices geared up for long-term sustainability, investments in quality equipment will be key to achieving both safety and sustainability goals.

*This piece was written by David Cheeseman, Chief Engineer of Oxair Gas Systems. Oxair is an ISO 9001 certified company focused on the design and manufacture of packaged oxygen PSA Systems, as well as Nitrogen PSA systems up to 1,000 Nm3/h.

AngloGold Ashanti confirms caving plans in Colombia

The Massmin 2020 crowd got a glimpse of just what will be required to build Colombia’s first underground caving mine during a presentation from AngloGold Ashanti’s Lammie Nienaber this week.

Nienaber, Manager of Geotechnical Engineering for the miner and the presenter of the ‘Building Colombia’s first caving mine’ paper authored by himself, AngloGold Ashanti Australia’s A McCaule and Caveman Consulting’s G Dunstan, went into some detail about how the company would extract the circa-8.7 Moz of gold equivalent from the deposit.

The Nuevo Chaquiro deposit is part of the Minera de Cobre Quebradona (MCQ) project, which is in the southwest of Antioquia, Colombia, around 104 km southwest of Medellin.

A feasibility study on MCQ is expected soon, but the 2019 prefeasibility study outlined a circa-$1 billion sublevel caving (SLC) project able to generate an internal rate of return of 15%. Using the SLC mining method, a production rate of 6.2 Mt/y was estimated, with a forecast life of mine of 23 years.

The MCQ deposit is a large, blind copper-gold-silver porphyry-style deposit with a ground surface elevation of 2,200 metres above sea level (masl, on mountain) and around 400 m of caprock above the economic mineralisation.

Due to the caving constraints of the deposit, the first production level to initiate caving (undercut) is expected to be located around 100 m below the top of the mineralisation at 1,675 masl (circa-525 m below the top of the mountain), with the mining block extended around 550 m in depth (20 production levels at 27.5 m interlevel spacings).

The main ore transfer horizon is located 75 m higher in elevation than the mine access portals at 1,080 masl and the proposed valley infrastructure. The initial mining block will be accessed by twin tunnels developed in parallel for 2 km at which point a single access ramp will branch up towards the undercut; the twin tunnels will continue another 3.7 km to the base of the SLC where the crushing and conveying facilities will be located.

The company is currently weighing up whether to use tunnel boring machines or drill and blast to establish these tunnels.

Nienaber confirmed the 20 level SLC panel cave layout would involve 161 km of lateral development and 14 km of vertical development. There would be six ore pass connections on each level, four of these being ‘primary’ and two acting as backups. The crusher would be located on the 1155 bottom production level.

Due to the ventilation requirements in Colombia the mining fleet selected for Quebradona is predominantly electric, Nienaber said, adding that the units will initially be electric cable loaders powered by 1,000 v infrastructure.

Fourteen tonne LHDs were selected for the production levels based on their speed, bucket size (enables side-to-side loading in the crosscut and identification of oversize material) and cable length, the authors said. On the transfer level, 25 t loaders were specified to accommodate the shorter tramming lengths and limited operating areas (there are a maximum of two loaders per side of the crusher due to the layout).

As battery technology improves in the coming years, the selection of loader sizes may change as additional options become available, according to the authors.

The selection of the present Sandvik fleet was predominantly based on the electric loaders and the OEM’s ability to provide other front-line development and production machines required to undertake SLC mining, the authors said.

This decision also accounted for the use of automation for the majority of production activities, with the use of a common platform seen as the most pragmatic option at this stage.

It has also been proposed that the maintenance of the machines be carried out by Sandvik under a maintenance and repair style contract since there is a heavy reliance on the OEM’s equipment and systems.

An integrated materials handling system for the SLC was designed from the ore pass grizzlies, located on the production levels, to the process plant.

Due to the length of the ore passes (up to 500 m), and the predicted comminution expected by the time the rock appears on the transfer level, larger than industry standard grizzly apertures of 1,500 mm have been selected.

The design criteria for the underground crusher was that it needed to reduce the ore to a size suitable for placement on the conveyor belt and delivery to the surface coarse ore stockpile, after which secondary crushing prior to delivery at the process plant will be undertaken.

Assuming the maximum size reduction ratio for the crusher of circa-6:1 at a throughput rate of 6.2 Mt/y, a 51 in (1,295 mm) gyratory crusher was selected. This crusher is also suitable to support block cave mining should the conversion of mining method occur, according to the authors.

The process plant will include high pressure grinding rolls as the main crushing unit on the surface, supported by a secondary crusher to deal with oversize material. The ore then feeds to a ball mill before being discharged to the flotation circuit.

The gold-enriched copper concentrate will be piped to the filter plant for drying and the removal of water down to a moisture content of 10%, according to the company, while the tailings will be segregated to pyrite and non-pyrite streams before being distributed to one of two filter presses.

Dry stacking of the tailings will be used, with the pyrite-bearing tailings being encapsulated within the larger inert tailings footprint.

With the feasibility study due before the end of the year – and, pending a successful outcome – the proposed site execution works could start in the September quarter of 2021, Nienaber said.