Tag Archives: copper

Macmahon expands underground work with Silver Lake Deflector contract

Macmahon Holdings’ underground mining division has been awarded a four-year contract with Silver Lake Resources to perform the mining works at the Deflector gold-copper mine in Western Australia.

A Macmahon subsidiary, GBF, has been providing underground mining services at the Deflector mine since mining commenced in early 2016. Macmahon acquired 100% of GBF in 2019, and this business is now an important part of the company’s strategy to expand in the underground mining services market, it said.

The company also recently had its stay extended at Silver Lake’s Mount Monger gold operations, in Western Australia.

The contract is a full service mining contract and, therefore, incorporates all underground development, ground support and production activities, including the provision of all labour and mobile mining equipment. Anticipated to run until April 2025, the contract is expected to generate around A$220 million ($170 million) in revenue for the company over this period.

Macmahon’s CEO and Managing Director, Michael Finnegan, said: “This new contract is an important milestone in our strategy to expand our underground business, and is a clear demonstration of the benefits we are now realising from the GBF acquisition.

“Importantly, the Deflector mine is a high-grade gold and copper asset in Western Australia, so is an attractive project in the current macro environment. We look forward to continuing to support the development of Deflector, and to achieving further scale in the underground market.”

Taseko Mines starts commercial construction move at Florence ISR copper project

Taseko Mines, having just completed a $400 million bond refinancing and fundraising program, is moving forward with developing a commercial operation at its Florence in-situ recovery (ISR) copper project in Arizona, USA.

Capital requirements for the commercial production facility at Florence, which followed an ISR pilot project, are estimated at $230 million.

Pending final regulatory approvals and financing, Taseko has previously stated it could start construction of the commercial operation this year, with first production in late 2022.

Stuart McDonald, President of Taseko, said: “With the majority of the required funding for our Florence Copper project now in hand, we are moving forward with final design engineering of the commercial production facility as well as procurement of certain critical components.”

McDonald said the company is continuing to advance discussions with potential joint venture partners at Florence, but its strong cash balance and improved Gibraltar mine cash flows from copper prices currently over $3.70/Ib ($8,159/t) means it has “numerous options available” to obtain the remaining funding.

Russell Hallbauer, CEO of Taseko, added on Florence: “Florence is one of the least capital-intensive copper production facilities in the world and, when fully ramped up, will produce 40,000 t of high-quality cathode copper annually for the US domestic market.

“It is a green project, with carbon emissions and water and energy consumption all dramatically lower than a conventional mine, and, with C1 operating costs of $0.90/Ib of copper, it will also be in the lowest quartile of the global cost curve.”

Peel Mining’s South Cobar preliminary flowsheet to factor in ore sorting

Peel Mining says positive results from ore sorting test work at the Southern Nights and Mallee Bull deposits, part of its 100%-owned South Cobar Project, in western New South Wales, Australia, provide encouragement for the inclusion of this pre-concentration technology into future process plant design.

So encouraged by this testing is Peel that it has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report for the project.

At the same time as this, Peel announced that GR Engineering had recently completed a preliminary process plant technical report for South Cobar that considers crushing, grinding, gravity, flotation and cyanidation process stages for the recovery of gold, silver, copper, lead and zinc from the various mineralisation styles within Peel’s deposits.

Meanwhile, the recently received positive preliminary ore sorting test work results from work undertaken on diamond drilling samples shows there is potential for improvements in the flowsheet.

The ore sorting test work, completed in conjunction with ongoing metallurgical studies, was undertaken by Steinert and TOMRA.

Steinert ’s test work on Southern Nights mineralisation demonstrated strong recovery and upgrade potential with two size range samples returning, on average, circa-93% Zn, circa-91% Pb, circa-91% Ag, circa-87% Cu and circa-82% Au recoveries to an average of circa-54% of the feed mass (circa-46% of feed mass rejection) increasing the lead and zinc grades by 61% and 64%, respectively.

TOMRA’s test work on Mallee Bull mineralisation achieved significant waste mass reductions while maintaining very high copper recoveries (≥95% for the higher-grade breccia copper and massive sulphide copper samples), the company said. A lower grade breccia copper sample upgraded from 0.59% Cu to 1.05% Cu with 77% Cu recovery and 56% mass rejection, it noted.

“Positive results from ore sorting at Southern Nights and Mallee Bull deposits provide encouragement for the inclusion of this pre-concentration technology into future process plant design and, as a result, Peel has engaged GR Engineering to integrate ore sorting technology into an updated processing plant technical report,” the company said.

Peel’s Executive Director of Mining, Jim Simpson, said: “The completion of the processing plant technical report by mineral processing solutions experts GR Engineering is a critical first step in understanding the potential composition of the milling infrastructure required for the company’s development plans.

“The detail presented in the report by GR is impressive and the report will form the basis for ongoing preliminary studies for the refinement and improvement of the processing plant design as new information comes to hand.

“We are also very pleased with the potential of ore sorting as part of any future South Cobar project hub’s processing route with initial test work pointing to the amenability of both Southern Nights and Mallee Bull mineralisation to separation using 3D-XRT ore-sorting technology, allowing for the simultaneous rejection of barren or waste material whilst retaining the bulk of contained metal, and in the process, upgrading the value of the ore.”

Simpson added: “Apart from reducing the overall feed mass by the rejection of waste at early stage, other benefits of ore sorting include potentially upgrading lower-grade mineralisation and reducing the size of the processing plant offering potentially reduced capital, power, water and tailings storage needs.”

Eriez HydroFloat technology to help improve recoveries at Newcrest’s Cadia operation

Eriez Flotation is to supply four HydroFloat® Separators to Newcrest Mining for use in Stage 2 of the miner’s Cadia Valley Operations (Cadia) expansion project in New South Wales, Australia.

This announcement follows the successful delivery, commissioning and ramp up of four Eriez CrossFlow Separators and two HydroFloats as part of the Cadia Coarse Particle Flotation demonstration plant in 2018.

Eriez Flotation Global Managing Director, Eric Wasmund, says: “When Stage 2 of the Cadia Expansion Project is complete, 100% of the Concentrator 1 tailings will be re-treated, significantly improving overall plant recovery for a coarser primary grind.”

The Stage 2 Cadia Expansion project primarily comprises the addition of a second coarse ore flotation circuit in Concentrator 1, using Eriez’s HydroFloat technology, and equipment upgrades in Concentrator 2, Newcrest said back in October. These changes are expected to see plant capacity go from 33 Mt/y to 35 Mt/y, while life of mine gold and copper recoveries could increase by 3.5% and 2.7%, respectively. Alongside this, the company was expecting a A$22/oz ($16/oz) drop in its all-in sustaining costs.

Newcrest is the first mining company to commercialise HydroFloat coarse particle flotation in sulphides and the first
in a tail scavenging application.

Wasmund added: “Eriez has been very fortunate to partner with Newcrest on coarse particle flotation. As partners we have learned many lessons together.”

Eriez-Australia Managing Director, James Cooke, noted: “During the commissioning of the demonstration plant, Eriez and Newcrest Mining worked closely together to perfect the technology. The decision was subsequently made to expand the application.”

Capstone prepares Cozamin for introduction of paste backfill, dry-stack tailings

An updated Technical Report on Capstone Mining’s Cozamin copper-silver mine in Zacatecas, Mexico, has shown the potential for a mine life extension to 2031, and a plan for dry-stack tailings and underground paste backfill. At the same time, the company says it is studying the use of “innovative mining techniques and enhanced pillar recovery” to make the most of existing reserves and resources.

The updated life of mine plan released outlined average annual copper production of 51.2 MIb (23,224 t) of copper and 1.6 Moz of silver production over 10 years at average C1 costs, including the 50% silver stream, of $1.02/Ib of payable copper. From 2021 to 2027, average annual production is slated to be 58.8 MIb of copper and 1.7 Moz of silver.

The company said a planned ramp-up to 3,780 t/d, or 1.38 Mt/y, by the end of March quarter is on track, with a new section of ramp to open the one-way traffic circuit to debottleneck the mine (pictured) completed in early December 2020, ahead of schedule.

Reserves increased by 39% and now stand at 14.1 Mt, relative to April 30, 2020. Contained copper and silver increased by 37% and 49%, respectively, with around half of this increase due to recovery of high-grade pillars using paste backfill, Capstone said.

The miner said “tailings management transformation” activities were progressing on schedule at site, including feasibility-level design and studies in support of permitting a filtered (dry stack) tailings storage facility.

“This conversion from a slurry tailings impoundment aligns with industry leading socio-environmental best practice for tailings management,” the company said.

Meanwhile, a prefeasibility study (PFS) for an underground paste backfill system was completed in December.

The study indicates a paste backfill system will allow ore extraction containing over 100 MIb of copper and 3.1 Moz of silver between 2023 and 2031, which would have otherwise been left as unmined pillars. The PFS design has a capital cost estimate ranging from $41-$45 million and an increase in operating costs of around $7.50/t of ore mined. Capstone says its management has approved the paste backfill project and work has commenced on procurement of long lead items.

The proposed paste backfill system includes a tailings filter plant, a paste mixing plant, twin boreholes to deliver paste underground and an underground distribution system. The system is expected to be commissioned starting in the December quarter of 2022, with ramp-up completed in the March quarter of 2023.

PFS design of these facilities was completed by Paterson & Cooke in December 2020 and a feasibility study is underway with completion expected in April 2021. Mine planning was completed by Cozamin, with design support provided by a geotechnical consultant, and paste backfill operational guidance provided by AMC Consultants.

Within the latest release, Capstone also flagged the initiation of its “Impact23 Growth” project, which has identified areas of exploration excellence, innovative mining techniques and enhanced pillar recovery at Cozamin.

“By 2023, the goal is to further extend mine life, increase environmental and safety standards, and improve operational efficiencies at Cozamin, utilising mineral resources already discovered in addition to testing new targets,” the company explained.

Included among the options are the innovative mining techniques for resource to reserve conversion flagged at the start of this story.

Capstone says a study will be initiated this year to assess alternative mining techniques with the objective of lowering costs and dilution to convert resources to reserves from the indicated resource base. The current mining methods are longitudinal longhole open stoping and AVOCA, with possible alternatives to be studied including cut-and-fill, drift-and-fill and longhole open stoping with ore sorting technology.

Brad Mercer, Capstone’s SVP and Chief Operating Officer, said: “The life of mine plan announced today maximises extraction of the orebody’s high-grade core by deferring stoping in this area until the paste backfill plant is in operation in 2023. Projected production averages nearly 60 MIb of copper per year for seven years at first quartile costs.

“The Impact23 Growth project that we are kickstarting today is aiming to demonstrate in a 2023 technical report how Cozamin can sustain these levels of performance well into the 2030s.”

Darren Pylot, Capstone’s President and CEO, added: “After 14 years in operation, the best years of Cozamin are ahead. The mine is world class with sustainable low costs and leading safety and environmental performance entrenched throughout the organisation. The growth initiatives are supported by an entrepreneurial fabric at Capstone, as we embrace innovation and technology to create high impact value for our shareholders.”

Byrnecut adds Carrapateena to OZ Minerals underground contract mining portfolio

OZ Minerals Ltd has changed underground mining contractor at its Carrapateena copper-gold mine in South Australia following Downer EDI’s move to divest its mining services businesses to MACA.

The company has now signed an agreement with Byrnecut Australia for the delivery of underground mining and associated mining services at Carrapateena. The two companies know each other well, with Byrnecut already carrying out underground mining services at OZ Minerals’ Prominent Hill for the past 10 years.

The five-year alliance-style contract with Byrnecut is valued at circa-A$130 million/y ($101 million/y), OZ Minerals said. Byrnecut has already commenced a seven-week mobilisation to the Carrapateena site and will assume full responsibility for mining services delivery from March 4, 2021.

“OZ Minerals, Byrnecut and Downer will work together during the transition period to ensure continuity of operational performance and development, and employee support and opportunities, with the objective of providing roles for the majority of the incumbent underground workforce,” the company said. “This transition will include the transfer of equipment from Downer to Byrnecut.”

Byrnecut will now provide underground mining services to both the Carrapateena and Prominent Hill mines.

“Byrnecut is a proven top-tier underground mining contractor who has been providing underground mining services to Prominent Hill for the past 10 years, with their Prominent Hill contract having been renewed in 2020,” OZ Minerals said.

The scope of work comprises all underground mining activity for the duration of the contract including production and development mining and associated mining services; and bedding in steady-state operations at nameplate site capacity.

Jervois Mining looks to POX leaching to boost SMP nickel-cobalt refinery recoveries

Jervois Mining says it plans to integrate a pressure oxidation leach (POX) circuit into the São Miguel Paulista nickel-cobalt refinery in Brazil.

Jervois paid the first tranche towards its acquisition of SMP refinery in December after announcing plans to acquire the refinery in September 2020. The acquisition aims to complement its 100%-owned Idaho Cobalt Operations (ICO) in the US, transforming Jervois into a vertically integrated producer capable of refining cobalt and nickel.

The company appointed Australia-based Elemental Engineering to commence sysCAD modelling of the SMP refinery flowsheet for optimisation of product integration, including hydroxides and carbonate products, oxides and sulphide concentrates as part of a feasibility study (FS) for SMP’s restart.

As a result of Elemental’s work, Jervois has determined it shall integrate a POX leach circuit at the refinery.

“The inclusion of the POX autoclave offers a number of advantages compared to roasting concentrates, namely high metal recovery, low overall operating costs, enhanced ESG metrics due to lower emissions and energy usage, improved refined product purity and compact installation footprint on site,” the company said. “Preliminary POX sighter testwork at SGS Perth Western Australia, in conjunction with Elemental’s work, returned satisfactory results.”

While POX comes with a higher capital expense than roasting alternatives, it is a commercially demonstrated technology with low technical risk, allowing Jervois to leverage its recently appointed commercial team, Jervois said. A POX autoclave better compliments the refinery flowsheet, unlocks sunk capital by debottlenecking the existing leach capacity and adds significant flexibility to future refinery feed options, it added.

Jervois will process sulphide concentrate produced from ICO via this integrated POX leach circuit, with Jervois’ commercial team actively pursuing supply contracts for nickel and cobalt intermediate products. The introduction of a POX autoclave opens up greater capacity to leach other hydroxide and carbonate feed products to maximise existing refinery capacity, the company said.

Third-party concentrates can also be potentially introduced into the POX to process with Jervois’s ICO concentrates. Early discussions with potential third-party suppliers of sulphide-based concentrates have been positive, with the company now openly engaging with suppliers to optimise the sizing and economics of front-end pre-treatment.

As part of this, a decision has been made to reserve the maximum amount of copper capacity at SMP refinery for third parties. A consequence is that ICO construction is being advanced on the basis of the production of separated cobalt and copper concentrates. Jervois’s engineering advisers, DRA Global and M3 Engineering, completed the ICO BFS on both bulk and separated concentrate flowsheets, with construction plans being implemented based on the production of cobalt concentrate (containing gold and low in copper) and a copper concentrate. Commercial terms were obtained for both separated products as part of the BFS.

Jervois says it and Companhia Brasileira de Alumínio (CBA), the current owner of the SMP refinery, continue to work expeditiously towards closing Jervois’ acquisition of SMP.

Jervois plans a measured and staged approach to the refinery facility restart. Initial refurbishment works will be completed to progress the processing of intermediate hydroxide and carbonate products followed by the integration of the POX leach circuit to align with ICO commissioning, it said.

Jervois is in discussions with suitably qualified engineering contractors that have the appropriate nickel and cobalt refining experience, have a significant presence in Brazil, and have recently completed a POX and metals plant installation, to award the BFS for the refinery restart. This formal tender process is underway.

Nornickel backs responsible sourcing and production practices with blockchain agreement

Norilsk Nickel says it is joining the Responsible Sourcing Blockchain Network (RSBN), an industry collaboration among members across the minerals supply chain using blockchain technology to support responsible sourcing and production practices from mine to market.

The move to join RSBN comes after Nornickel announced a broad strategy to use sophisticated digital technologies to create a customer-centric supply chain, which would include metal-backed tokens on the global Atomyze platform, a tokenisation platform that represents physical assets in digital form. Both the Atomyze and RSBN platforms were developed by leveraging Hyperledger technology, with IBM’s participation, the PGM and base metal miner said.

With Nornickel joining the RSBN, a series of its supply chains will be audited annually against key responsible sourcing requirements by RCS Global. The audits cover each stage of the company’s vertically integrated operations from mines in Russia to refineries in Finland and Russia.

Once audited against responsible sourcing requirements, each supply chain will be brought on to the RSBN and an “immutable audit data” trail will be captured on the platform, proving responsible nickel and cobalt production, its maintenance and its ethical provenance.

“Integration with RSBN is yet another step for Nornickel towards achieving greater business sustainability by creating a permanent record of minerals on the blockchain,” the company said.

At a later development stage, data such as upstream carbon intensity and other ESG attributes will be tracked, it added.

Built on IBM Blockchain technology and powered by the Linux Foundation’s Hyperledger Fabric, the RSBN platform helps improve transparency in the mineral supply chain by providing a highly secure and immutable record that can be shared with specified members of the network, Nornickel says. Additionally, RCS Global Group assesses each participating entity both initially and annually against responsible sourcing requirements set by the Organization for Economic Cooperation and Development and those enshrined by key industry bodies, including the Responsible Minerals Initiative.

Anton Berlin, Nornickel’s Vice President, Sales and Distribution, said: “As one of the largest industry groups globally and the producer of the minerals essential for the transition to a carbon-free world, Nornickel is well aware of its responsibility to make the metals supply chains sustainable and highly transparent. We believe that the digital technologies of RSBN and Atomyze will create the path for Nornickel and its partners to participate in a circular value chain, tracing commodity flows in near real time as well as replacing cumbersome paperwork.”

RCS Global CEO, Dr Nicholas Garrett, added: “The RSBN has proven that responsible sourcing can be traced and documented using blockchain technology. Assuring Nornickel’s supply chains is another milestone engagement for RCS Global and Nornickel’s commitment to the RSBN and demonstrates momentum for blockchain backed responsible sourcing platform in the metals sector.”

Manish Chawla, Global Managing Director, Chemicals, Petroleum & Industrial Products, IBM, said: “Norilsk Nickel is an important addition to the Responsible Sourcing Blockchain Network and we look forward to their contributions to help advance the assurance for responsible sourcing and the group’s sustainability goals that have a direct impact on successful and accountable development for entire industries.”

RSBN is designed to be adopted across industries by original equipment manufacturers in automotive, electronics, aerospace and defence as well as their supply chain partners such as mining companies and battery manufacturers.

Canada Nickel investigates Crawford processing potential at Glencore’s Kidd concentrator

Canada Nickel Co says it has entered into a non-binding Memorandum of Understanding (MoU) with Glencore Canada that could see material mined from Canada Nickel’s Crawford nickel-cobalt sulphide project treated and processed at Glencore’s Kidd concentrator and metallurgical site in Timmins, Ontario.

Crawford, around 40 km north of Glencore’s operations, hosts a 657 Mt measured and indicated resource grading 0.26% Ni and 0.013% Co. It is currently the subject of a preliminary economic assessment (PEA).

The Kidd operations consisting of the Kidd metallurgical site and the Kidd mine. The concentrator is located on the property of the Kidd Metallurgical Site, 27 km east of Timmins, in the Townships of Hoyle and Matheson. Built in 1966 with numerous upgrades over the years, the concentrator currently processes metal ore to produce copper and zinc concentrates. The facility has a design rated capacity of 12,500 t/d and is fully permitted with water taking and discharge permits and thickened tailings storage. The site has incoming and outgoing rail service via Ontario Northland Railway.

Canada Nickel says it has completed an initial high-level assessment of the potential arrangements envisaged under the MoU and will proceed with a detailed study on the potential for upgrading excess capacity at the Kidd concentrator and/or using the existing infrastructure in place at the Kidd metallurgical site for milling and further processing the nickel-cobalt and magnetite concentrates that are expected to be produced from Crawford.

Mark Selby, Chair and CEO of Canada Nickel, said: “The opportunity to utilise the excess capacity and existing infrastructure at the Kidd Met Site provides the potential to allow a faster, simpler, smaller scale start-up of Crawford at a vastly lower capital cost while the company continues to permit and develop the much larger-scale project currently being contemplated.

“Given the potential for this significant change in the scope of the project start-up, the release of the PEA will be delayed until the end of March 2021 to allow this option, if successful, to be incorporated.”

This study is being led by Ausenco Engineering Canada Inc, which is also supporting the assessment of the Kidd Met Site facilities.

Canada Nickel’s plans include the development of a “Zero-Carbon footprint operation”. This considers the use of electric rope shovels and trolley trucks which utilise electricity, rather than diesel fuel, as a power source wherever possible, along with a natural mineral carbonation approach for the deposition of waste rock and tailings during mining to allow material to absorb CO2.

Codelco to extend life of Salvador Division with Rajo Inca copper project

The Codelco board has approved the development of the $1.383 billion Rajo Inca structural project, part of its Salvador Division in Chile’s Atacama.

The figure is 33% less than the investment contemplated by Codelco in 2014 thanks to the use and optimisation of existing infrastructure within the division, especially in the mine areas and the tailings deposit. Ongoing maintenance of the concentrator and hydrometallurgical plants has also helped bring down this figure.

The savings were also achieved through the planned reuse of mining equipment. When it enters operations, Rajo Inca will require 25-30 300-ton capacity trucks, hydraulic shovels and large tonnage front end loaders. Most of this equipment will come from other Codelco divisions, the company says.

The structural project includes a 22-month pre-stripping period and a seven-month ramp up of the concentrator plant. Commissioning will begin in the second half of 2022, with production reaching a annualised rate of 90,000 t/y of copper in the first half of 2023.

After the favourable Environmental Qualification Resolution obtained in February 2020 and the approval of the funds by the board of directors, the structural project will mean a rebirth for Salvador, as it will become a more modern, “technologised”, sustainable and productive operation, the company said. Its development will add 47 more years of life to this camp.

The Salvador Division has operated since 1959 with underground mining and three small open pits. With the latest investment, production will increase by 50% from 60,000 t/y to 95,000 t/y of fine copper.