Tag Archives: Silver

Turquoise Hill and Rio Tinto sign Oyu Tolgoi UG funding HoA, agree to end arbitration

Turquoise Hill Resources and Rio Tinto have entered into a binding Heads of Agreement (HoA) to provide an updated funding plan for the completion of the Oyu Tolgoi underground copper-gold project in Mongolia.

The funding plan is designed to address the estimated remaining funding requirement of around $2.3 billion and replaces the non-binding Memorandum of Understanding that Rio and Turquoise Hill previously entered into on September 9, 2020.

Under the HoA, subject to securing approval by Oyu Tolgoi LLC, the project joint venture, and any required support from the Government of Mongolia, Turquoise Hill and Rio Tinto will:

  • Pursue re-profiling of existing project debt to better align with the revised mine plan, project timing and cash flows to reduce the currently projected funding requirements of OT by up to $1.4 billion; and
  • Seek to raise up to $500 million in senior supplemental debt (SSD) under the existing project financing arrangements from selected international financial institutions.

In addition, Rio Tinto has committed to address any potential shortfalls from the re-profiling and additional SSD of up to $750 million by providing a senior co-lending facility on the same terms as Oyu Tolgoi’s project financing, while Turquoise Hill has committed to complete an equity offering of up to $500 million.

An updated feasibility study on the underground expansion at Oyu Tolgoi from June 2020 included a delay of 21 to 29 months for first sustainable production compared with the original 2016 feasibility study guidance and an increase of $1.3-$1.8 billion from the original $5.3 billion development capital. The process also saw 1.22 Mt of copper, 850,000 oz of gold and 7.01 Moz of silver removed from the Hugo Dummett North reserve base compared with the December 31, 2019 calculation, with some 80,000 t of copper, 70,000 oz of gold and 550,000 oz of silver added to the Hugo Dummett North Extension reserve base.

Since this announcement, Rio, Turquoise Hill and the Government of Mongolia have been trying to agree on a new funding pact for the sustainable development of the underground operation, which, in combination with open-pit mining, could produce around 500,000 t/y of copper at full capacity.

Steve Thibeault, Interim Chief Executive Officer of Turquoise Hill, said: “We are pleased to have reached a constructive and equitable agreement with Rio Tinto to fund the Oyu Tolgoi underground development. With a binding funding agreement now in place that sets out a process along a known timeline, we will be able to move ahead as expeditiously as possible with the development of the underground project at Oyu Tolgoi.

“We remain committed to continue delivering a benefit to all stakeholders, including Mongolia and its citizens, and to delivering significant long-term value for Turquoise Hill as this project progresses.”

Rio Tinto Copper Chief Executive Bold Baatar, added: “This agreement and alignment with Turquoise Hill represents a major milestone in the continued development of Oyu Tolgoi, which is expected to become one of the world’s largest copper mines and a significant contributor to the Mongolian economy for years to come. Commencing the re-profiling whilst concurrently listening, engaging and resolving the concerns of the Government of Mongolia are critical steps to maintaining momentum on the timely delivery of the Oyu Tolgoi Underground project.”

Following the HoA, Turquoise Hill and Rio have agreed to obtain an order dismissing the current arbitration on a “without prejudice basis” and without costs, including an order vacating the interim measures order, the companies said.

Telson Mining ready to experiment with metallurgical innovations at Campo Morado

Telson Mining, following a strong quarter of production from the Campo Morado mine, in Guerrero State, Mexico, is making plans to boost throughput and recoveries through the potential use of grinding, leaching and flotation technologies from the likes of Maelgwyn Mineral Services, Core Group and Glencore Technology.

The mine’s throughput averaged out at 58,100 t/mth in the March quarter, with total throughput for the quarter of 174,400 t being 4% higher than the December quarter. Some 11,013 t of zinc concentrate and 1,907 t of lead concentrate was produced over the period, compared with 9,974 t and 1,916 t, respectively, in the previous quarter.

Gold, silver, lead and zinc recoveries all improved, quarter-on-quarter, in the first three months of the year, the company added.

Ralph Shearing, Telson CEO and President, said: “These strong first quarter results continue to reflect our steady progression of improving the throughput and recoveries at Campo Morado. To this end, management intends to initiate a rigorous metallurgical testing program to advance through second phase testing the Leachox™ Process of Maelgwyn Mineral Services and the Albion Process™ of Core Group, both of which returned positive test results in first phase testing.”

He said this metallurgical testing program will also study the ability to increase base metal recoveries at microfine grinding with flotation recovery using Imhoflot Flotation (also Maelgwyn) and Jameson Cell (Glencore Technology) flotation technologies, both designed for such purposes.

“We are confident that additional recovery improvements are available utilising these exciting modern technologies which, if successful, can provide increased revenue streams,” Shearing added.

Maelgwyn’s Leachox Process consists of several Maelgwyn proprietary processes linked together including Imhoflot G-Cell flotation technology, ultra-fine grinding using the Ro-Star mill, Aachen Reactors and Aachen assisted cyanide destruction.

The Albion Process, meanwhile, is a combination of ultrafine grinding and oxidative leaching at atmospheric pressure. The feed to the Albion Process is refractory base or precious metal concentrates, where the sulphides in the feed are oxidised and liberated, allowing the target metals to be recovered by conventional means.

New Major Drilling rod handling rigs start turning at Hecla’s San Sebastian mine

Two new Major Drilling EF-75 drills have arrived and are now turning at Hecla Mining’s San Sebastian mine in Durango, Mexico, the drilling services company says.

The drills arrived in March and are part of Major Drilling’s fleet improvements, adding innovative rod handling capability to the project, it said.

“We are thankful that we are partnered with a company like Major Drilling that can provide newer, innovative drills,” Stephen Redak, Exploration Manager Mexico, Hecla Mining, said.

Hecla’s San Sebastian property is a silver and gold mine, where exploration work is underway in two main veins. Using these new drills at the San Sebastian project enhances Major Drilling’s 12-year history with Hecla in Mexico. This has seen more than 354,000 m drilled since 2009.

Major Drilling’s EF-75 core drill is new equipment for the Mexico branch. It combines safety with a high level of productivity, according to the company.

With the rod manipulator, operators benefit from rod handling, horizontal stacking and a safety screen to protect them while lifting and lowering rods. The rig is capable of depths of up to 2,700 m.

Workers are protected by rod handling innovation, and they improve results using a unique mast designed for accurate core orientation, the company says.

David Boucher, Major Drilling Mexico General Manager, said: “Hecla has been a long-time client of ours in Mexico, and we are very excited to bring these new drills out in Durango to really see what they can do at San Sebastian. We are very happy to have this equipment turning in Mexico.”

Major Drilling’s USA Division previously partnered with Hecla at the Fire Creek Mine in Nevada (now under care and maintenance). The company’s exploration teams have also drilled at Hecla surface exploration projects in other locations in the western USA.

Foran Mining assembles FS team for ‘world first’ carbon neutral copper mine project

Foran Mining says it has bolstered the design team for its ongoing definitive feasibility study at the McIlvenna Bay project, in Saskatchewan, Canada, providing the company with the technical expertise to execute on its strategy of building the world’s first copper mine designed to be “carbon neutral” from day one of production.

The advisors are anticipated to employ a range of technologies and initiatives in the design of the mine and processing facilities to materially reduce greenhouse gas emissions and the environmental impact of the operations.

Foran says its due diligence to date has highlighted the potentially superior returns achievable through implementing this strategy, while the use of battery-electric vehicles will also be safer for employees, reducing risk of injury and physical stressors, such as vibration and noise.

The FS team includes experts from:

  • Stantec – mine design and engineering;
  • Knight Piésold Ltd – tailings storage facility design;
  • Halyard Inc – process plant design;
  • Micon International Limited – resource estimate;
  • Base Metallurgical Laboratories Ltd – metallurgical testing;
  • Canada North Environmental Services Ltd – environmental; and
  • Synergy Enterprises – sustainability and carbon accounting

Dan Myerson, Executive Chair of Foran, said: “The appointment of these world-class environmental and engineering specialists reflects our ambition to develop a technically and economically compelling solution to the environmental and social challenges which have been traditionally associated with the sector. We are therefore thrilled that professionals of this calibre have agreed to support us on this journey.”

He added: “Together, we intend to ensure that our operations emit net zero greenhouse gases and set new safety benchmarks for the industry, while also ensuring that the local community and the broader Canadian population benefit from our operations. The responsible production of copper and zinc is critical as the world transitions to a low carbon future; these metals are used in the production of renewable energy assets and electronic industries, for example. We look forward to providing more updates, in relation to our infill and expansion drilling, as well as announcing more detailed plans about how we will be putting our ambitions into practice.”

The 2020 prefeasibility study on McIlvenna Bay envisaged a 3,600 t/d underground operation with on‐site crushing and mineral processing facilities, a paste plant and filtered tailings storage facility. It considered a nine-year life of mine and scheduled treatment of the full reserve of 11.34 Mt grading 4.01% Zn, 1.14% Cu, 0.54 g/t Au and 20.97 g/t Ag. It also included plans for McIlvenna Bay to be an early adopter of battery-electric haul trucks.

Foran recently commenced its largest drill program ever (pictured), with over 30,000 m of infill and expansion drilling in the deposit. This has been designed to maximise the conversion of the current inferred resource to the indicated resource category, which can then be interrogated for inclusion in the updated reserve statement.

Foran says the feasibility study will, among other things, look to:

  • Further optimise and detail the McIlvenna Bay project engineering, including the estimation of reserves, mine design, stope sequence, development and production schedules;
  • Refine power and equipment requirements to support the company’s commitment to carbon neutral operations;
  • Update and detail the design and feasibility of the tailings desulphurisation process, dry stack storage facility and cemented paste backfill processes;
  • Provide detailed construction scheduling, including optimisations that would arise from pre-fabrication and/or modular (off-site) construction to the greatest extent possible;
  • Identify further mine optimisation to increase productivity and reduce operational expenditures; and
  • Consider equipment usage and activities where greenhouse gas emissions can be eliminated, reduced or offset to ensure that McIlvenna Bay is a carbon neutral operation.

Hycroft Mining continues evaluation of novel sulphide heap oxidation/leach process

After testing out a “novel” oxidation and leaching process at the Hycroft Mine in Nevada, USA, Hycroft Mining Holding Corp is making plans to go back to a conventional oxide leaching setup in 2021.

The company produced 27,392 oz of gold and 178,836 oz of silver in 2020, an almost three-fold increase over 2019. It hit these numbers while operating at a pre-commercial scale using the novel process, which oxidises sulphides ahead of leaching.

It is now planning for run-of-mine production of 45,000-55,000 oz of gold and 400,000-450,000 oz of silver in 2021 using conventional cyanide heap leach.

It is anticipated that mining in the first four months of 2021 will be performed using the existing Hycroft fleet and a rental fleet, moving approximately 1.5 Mt/mth of ore and waste. For the remainder of the year, Hycroft intends to mine some 500,000 t of oxide and transitional ore and waste per month with a more cost-effective mining fleet.

Diane R Garrett, President & Chief Executive Officer, reflected on the results: “2020 was an important year for Hycroft as the company continued to focus on the restart of the Hycroft Mine. Throughout the year, we advanced work on the proprietary two-stage sulphide heap oxidation and leach process and made several important findings that will need to be addressed prior to our implementing the novel technology on a commercial scale.

“In 2021, we expect to mine predominantly oxide and transition material, which are more economic when treated using a conventional run-of-mine heap leaching method, which gives us the opportunity to continue to refine the operating parameters and flowsheet for the new heap leach pad and novel process. While the company continued to make significant progress in better understanding this proprietary process and its application on a commercial scale, the past year also presented some operational challenges, including learning to navigate in a newly emerged COVID-19 world.”

In the last few months, Hycroft says it has worked alongside consultants to identify and investigate opportunities for improvements in operating parameters for the two-stage sulphide heap oxidisation and leach process. The result of the work to date has identified several items that were not considered or included in the original plan and design but are critical to the success of this process. These findings include:

  • Adding a forced air injection system for the leach pad which is a key component of the oxidation process;
  • Developing a system for segregating solution flows to and from the heap leach pad to avoid co-mingling of solutions among heap lifts and ore processing stages that negatively impact recoveries and conditions on the leach pads;
  • Identifying that the finer crushed material requires agglomeration in order to achieve optimal permeability and gold/silver recoveries;
  • Understanding that higher soda ash, caustic soda, and cyanide consumption will be required which Hycroft experienced throughout the 2020 pre-commercial test pad programs and recently confirmed through the review of the test work;
  • Determining that some transitional ores are more economically attractive when processed as direct leach, run-of-mine material; and
  • Concluding that additional variability metallurgical and mineralogy studies will be required to better understand each of the geometallurgical domains in the orebody. While there was some variability work completed in the past, the recent test work has revealed that additional variability test work and compositing is necessary to fully understand the geometallurgy of each domain, and that additional sampling, including sampling below the water table where the predominance of the sulphide resources exist, is required given the complexity and variability of the large orebody.

The additional variability test work will also include detailed mineralogy studies as it is important to understand the role other minerals may play in the overall oxidation process and to enhance Hycroft’s ability to measure oxidation rates accurately and consistently, it said.

The team at Hycroft has developed an approximate $10 million program for drilling and additional metallurgical and mineralogical studies in 2021. This program of work has been approved by the Board of Directors of Hycroft and can be funded from existing cash and Hycroft’s current operating plans.

Hycroft expects to mine and stockpile at least 300,000 tons (272,155 t) of sulphide ore in 2021 that, once sufficient additional work on the novel process has been completed, will be available for testing to further refine operating parameters and measure its performance for large scale application of the oxidation heap leach.

Garrett added: “2021 is a foundational year designed to advance the work necessary in preparation for larger-scale sulphide operations. The team is working diligently to optimise current and future heap leach mine plans and to evaluate all opportunities for more profitable mine plans in the near and medium term. This work involves taking a ‘ground up’ approach working from the orebody out. The company’s prior plan was developed using a $1,200/oz gold price pit shell which leaves profitable ore behind in the current gold and silver price environment. By running pit shells at recent gold and silver prices, we have identified additional areas of oxide mineralisation that can generate cash flows over the next several years and we have already begun to identify areas of higher-grade mineralisation that will become important for mine sequencing and further improving cash flows prior to accessing sulphide material.”

As the company considers life-of-mine development and planning for the Hycroft deposit, particularly in the current gold and silver price environment, Hycroft says it is prudent to evaluate proven processing technologies for treating some ore types that may be more profitable than only using the two-stage sulphide heap oxidation and leaching process.

Potential opportunities being examined by the company in 2021 include: developing an understanding of the grade range distribution of the sulphide material; completing on-going work on the higher-grade areas of Hycroft; and following up on historical high-grade intercepts.

In order to capitalise on these potential opportunities, which take advantage of the current commodity price environment, Hycroft believes that it should also evaluate the benefits of a multi-process operation. Long-term operating scenarios may include conventional run-of-mine cyanide heap leaching for the oxide and transitional material, sulphide heap oxidation and leaching using the novel process, and an appropriately sized milling and flotation plant for processing the higher-grade ranges of sulphide material.

“The company believes that the plan it has put in place for 2021 will provide the new team the time to fully consider and evaluate these opportunities and make any necessary changes to improve the leach pads, process plants and process flowsheet, maintain and develop its workforce, and advance the project, in order to further enhance the value of the project,” it said. “As the test work advances and alternative processes are considered, the company expects to perform technical studies and trade-off evaluations which may result in an updated feasibility study.”

Rio Tinto Kennecott to recover tellurium from copper smelting

Rio Tinto is to construct a new plant that will recover tellurium, a critical mineral used in solar panels, from copper refining at its Kennecott mine near Salt Lake City, Utah.

The company is investing $2.9 million to set up the plant, which will recover tellurium as a by-product of copper smelting, extracting a valuable mineral from waste streams. The plant will have a capacity to produce around 20 t/y of tellurium, the miner said.

Rio expects to begin production of tellurium in the December quarter of 2021, creating a new North American supply chain for the critical mineral.

Tellurium is an essential component of cadmium telluride, a semiconductor used to manufacture thin film photovoltaic solar panels. Thin films made of this compound can efficiently convert sunlight into electricity, according to the miner. Tellurium can also be used as an additive to steel and copper to improve machinability, making these metals easier to cut. It can also be added to lead to increase resistance to sulphuric acid, vibration and fatigue.

Rio Tinto Kennecott Managing Director, Gaby Poirier, said: “The minerals and metals we produce are essential to accelerate the transition to renewable energy. Adding tellurium to our product portfolio provides customers in North America with a secure and reliable source of tellurium produced at the highest environmental and labour standards with renewable energy. Rio Tinto is committed to using innovation to reduce waste in our production process and extract as much value as possible from the material that we mine and process.”

Utah Governor, Spencer Cox, said: “With abundant natural resources, Utah is ideally positioned to help supply the critical minerals essential to maintain American manufacturing competitiveness. Rio Tinto’s smelter at Kennecott is one of only two that is capable of producing copper and other critical minerals. The new tellurium plant is another valuable contribution to critical mineral independence and energy security in the US”

Along with producing almost 20% of US copper, Kennecott’s smelting process also recovers gold, silver, lead carbonate, platinum, palladium and selenium, while molybdenum is recovered from the Copperton concentrator. In total, nine products are currently recovered from the ore extracted at Kennecott.

Rio Tinto is a partner with the US Department of Energy’s Critical Materials Institute (CMI) and works closely with CMI experts to discover further ways to economically recover critical mineral by-products such as rhenium, tellurium and lithium. The company is also investing in new facilities to extract battery-grade lithium from waste rock at its Boron, California mine site and high quality scandium oxide from waste streams at its metallurgical complex in Sorel-Tracy, Quebec.

Polymetal 2020 profits rise as it accelerates ESG efforts

Polymetal recorded a strong set of financials in 2020, with its revenue, adjusted EBITDA and net earnings metrics all benefitting from higher production volumes and commodity prices.

Revenue increased by 28% year-on-year to $2.87 billion, adjusted EBITDA rose 57% to $1.69 billion and net earnings hit a record $1.09 billion in 2020.

The company’s 2020 gold-equivalent output amounted to 1.56 Moz, a 4% increase year-on-year and 4% above the original production guidance of 1.5 Moz. Strong contributions from its Kyzyl, Varvara and Albazino mines offset a planned grade decline at Voro, as well as lower production at Svetloye, the company said.

While production rose, the company’s greenhouse gas emissions intensity reduced by 4%, Polymetal said. It attributed this to energy efficiency initiatives, switching its mining fleet to electric vehicles, a shift from diesel to grid energy sources and green energy contracts.

Back in December, SMT Scharf AG signed an agreement with Polymetal to develop and produce battery-electric powered LHDs and mid-range underground trucks as prototypes for its gold and silver mines, with these units to be delivered to the company by October 2021.

Polymetal’s environmental, social and governance efforts did not stop there.

In 2020, the company invested $29 million at its Omolon hub in the Magadan region of Russia. This capital expenditure was mainly related to the construction of a dry tailings storage facility and engineering and preparatory works for a 2.5 MW solar plant (due to come online this year). This will be joined by another 5-10 MW solar facility at its Kyzyl operation (Kazakhstan) in 2022.

On its other tailings facilities, Polymetal said: “We operate eight tailings dams in Russia and Kazakhstan; each is rigorously monitored daily. We are confident that any emergency dam failure would have no impact on local communities and employees.

“We welcome the new Global Industry Standard on Tailings Management and have committed to achieving compliance in all operations by 2023.”

In addition to state authority inspections of these facilities, the company conducted an independent third-party audit of its Mayskoye (Chukotka, Russia) tailings site, which was carried out virtually, due to COVID-19 restrictions, by Knight Piésold Ltd. “To further improve tailings safety and minimise the risk of the possibility of dam failure, we are shifting towards dry stack storage methods,” it said.

“Such facilities are already in operation at our Amursk and Voro (pictured filter press) mines, and will be extended to Omolon (2021), Nezhda (2021), POX-2 (2022), Dukat (2024) and Veduga (2025).”

Bluestone widens production plans with Cerro Blanco open-pit mining PEA

Bluestone Resources has come out with a new open-pit mining plan for its Cerro Blanco project in south-eastern Guatemala that effectively doubles production and triples the potential investor returns from the gold-silver asset.

The preliminary economic assessment on Cerro Blanco, which comes just under 11 months after entering into an agreement with G Mining Services covering basic engineering and overall project optimisation efforts for the project, outlines a project able to produce 231,000 oz of gold at an all-in sustaining cost of $642/oz Au over the 11-year life of mine. This is based on a 15,000 t/d operation with a $548 million initial capital expenditure bill.

Using a base case gold price of $1,550/oz and silver price of $20/oz, an after-tax net present value (5% discount) of $907 million was calculated.

The numbers are significantly different from what the company outlined in a previous feasibility study on Cerro Blanco, completed by a consortium of independent consultants led by JDS Energy & Mining. This showed an average output of 113,000 oz/y of gold at an all-in sustaining cost of $579/oz and a capital cost of $196 million (including contingency).

Using a base case of $1,250/oz gold and $18/oz silver, this underground project was estimated to generate a post-tax net present value (5% discount) of $241 million.

Bluestone said on the PEA publication: “The recent completion of advanced engineering and optimisation work has significantly enhanced the understanding of the project and presented an opportunity to capitalise on its near-surface, high-grade mineralisation through an open-pit development scenario. This is a major change to Bluestone’s corporate strategy that will fully maximise the value of the Cerro Blanco gold project for all stakeholders.”

David Cass, Vice President of Exploration, added: “The pivot to surface mining is a culmination of our increased understanding of the geology and grade distribution that will realise the full potential of the Cerro Blanco low-sulphidation mineralisation. The inverted wedge shape of the deposit with its upper half forming the Cerro Blanco hill lends itself to surface mining with a low strip ratio.”

The project currently hosts 3 Moz of gold in the measured and indicated resource category and 250,000 oz of gold in the inferred mineral resource category.

The open-pit mining scenario envisages an owner-operated mining fleet using 65-t trucks matched with 7 cu.m hydraulic shovels supported by 8.2 cu.m wheel loaders. Mill feed will be trucked to a primary crusher located to the east of the main pit. Waste totalling 123.5 Mt will be placed in a waste storage facility.

In terms of processing, the PEA looks at treating 5.04 Mt/y of mineralised material at an average feed grade of 1.6 g/t Au and 7.26 g/t Ag through a conventional cyanide leach process plant to produce doré. The flowsheet is very similar to the previous underground mine option and includes primary crushing, single train SAG mill and ball mill to produce a target grind size of 80% passing 53 microns, atmospheric pre-oxidation, 48-hour cyanide leach, carbon-in-pulp carousel adsorption circuit, Zadra elution circuit, gold room and filtered tailings. Based on PEA metallurgical test work, the expected recoveries are 91% for gold and 85% for silver.

Filtered tailings will be configured in a dry-stack facility and eliminate the need for the construction and operation of a traditional tailings impoundment, the company says.

“The adoption of this technology (dry stacking) puts the Cerro Blanco project at the forefront of responsible mining practices being adopted for the future of sustainable mining globally,” it added.

Galena signs up Contract Power for hybrid power gen facility at Abra JV

Abra Mining Pty Ltd, the joint venture company behind the Abra base metals project, has executed a power purchase agreement (PPA) with Contract Power Australia that could see the construction and operation of a hybrid power generation facility made up of a natural gas and solar energy array at the Western Australia project.

Announcing the PPA, Galena Mining, which owns 77.28% of the project, said Contract Power will build, own and operate an integrated hybrid power generation facility combining a 10 MW natural gas fired power station, a 6 MW solar array, 2 MW of battery energy storage and a 900 Kl LNG storage and regasification facility.

Power will be purchased by Abra under the PPA for an initial term of 16-years (extendable), it said.

Galena Managing Director, Alex Molyneux, said: “We’re pleased to partner with Contract Power on a clean, cost-effective power solution for Abra. Integrating solar with relatively clean natural gas instead of diesel achieves a marked reduction in Abra’s carbon footprint compared to alternatives considered in the tender process.

“Pleasingly, the design also offered the most cost-effective solution, in line with our feasibility study estimates.”

This definitive feasibility study outlined development of a mine and processing facility with a 16-year life producing a high-value, high-grade lead-silver concentrate containing around 95,000 t/y of lead and 805,000 oz/y of silver after ramp-up.

A Western Australia-based company wholly-owned by Pacific Energy Ltd, Contract Power specialises in the design, construction and operation of remote power stations for the mining and government sectors.

Contract Power has operated power stations around Australia under turnkey build-own-operate arrangements since 1999, and recent projects include a 56 MW gas fired power station for Mineral Resources Ltd’s Wodgina lithium project, a 18 MW gas fired station for Capricorn Resources’ Karlawinda project and a 18 MW gas and diesel power station at Wiluna Mining Corp‘s Wiluna gold project.

Contract Power’s Managing Director, Leon Hodges, said: “We are very pleased to be working with Galena on this important project and look forward to rewarding their confidence by delivering a world-class hybrid power station.

“Contract Power’s combined LNG and renewables integration capability has allowed our design team to maximise solar penetration as high as the economics and technology allows, providing the Abra project with the highest reliability and lowest cost of power on an unsubsidised basis.”

The PPA remains subject to the condition of Abra Mining Pty Ltd proceeding to final investment decision for the project, Galena said.

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.”