Tag Archives: Silver

Endeavour Silver centralises, standardises Terronera process management with ARES PRISM

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Endeavour Silver has selected ARES PRISM project controls software for use on its Terronera silver project in Mexico to, ARES PRISM says, reduce manual labour, standardise processes and workflows, and improve project data integration.

Terronera was acquired in 2010, and, according to a recent pre-feasibility study, has the potential to produce around 3 Moz/y of silver and 33,000 oz/y of gold over an initial 10-year mine life.

ARES PRISM project controls software has a proven track record and is used throughout the mining industry at more than 80% of the world’s top mining organisations, the company claims.

Andres Zavaleta, Project Management Consultant with Endeavour Silver, said: “Our objective was to establish a centralised system that could be used from the beginning of the project to standardise processes and improve the flow of project data allowing for increased efficiency and better project delivery. ARES PRISM can fully integrate with our current ERP system to enable Endeavour Silver to create standardised workflows and processes.”

Endeavour Silver is implementing the full PRISM G2 software suite, which includes the cost management, engineering, contracts, procurement and field management modules. Alongside this, it will implement PRISM Docs and PRISM Dashboard.

“PRISM Docs will enable their teams to find, share and control business documents, while PRISM Dashboard will provide them a series of pre-designed dashboard views and reports for visually showing progress and performance information,” the company said.

Endeavour Silver has also elected to implement PRISM Go, a web-based extension that allows remote access into a project’s core data set and limited portal access for third-party contractors for project progression in a secure environment.

Geoffrey Stubson, CFO of ARES Project Management, said: “We find that many project organisations are limited by data silos. But in choosing to implement nearly the entire ARES PRISM project software suite, Endeavour Silver has taken a strong initiative to eliminate silos and get the most of their project data while saving time and costs developing the Terronera mine.”

Abra project heads for first lead-silver production in 2023

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The Abra base metals project in Western Australia is racing forward to first production in 2023 after the project owners signed off a positive final investment decision (FID) for the mine’s development.

The FID was made following the satisfaction of key conditions to draw in excess of $30 million under a debt facility.

As of May 31, 2021, the project is 17% complete, with completed works including: construction and commissioning of a 280-unit mine site village; mining of the box cut (pictured); box cut ground support works; installation of site communications; and various site clearing, roadworks and civil works.

“As a result, Abra is largely prepared for the deployment of key contractors for the construction of the plant and auxiliary infrastructure, and deployment of the underground mining contractor,” Galena Mining, the 77.28% owner of the project, said.

Among the key contractors at Abra is GR Engineering Services, which is set to deliver a 1.2 Mt/y lead sulphide flotation process plant and ancillary infrastructure under a A$75 million ($58 million) guaranteed maximum price arrangement. The underground mining services contract has been awarded to a tier one Australian mining contractor, Galena said without naming the contract recipient.

“Under the current project schedule, procurement of certain long-lead items will take place immediately,” Galena said. “The underground mining contractor is expected to initiate the portal and decline development in the third (September) quarter of 2021 calendar year and physical on-site plant construction is expected to commence in the fourth (December) quarter of 2021 calendar year.”

Related to the decision to move ahead with development, Galena said it was appointing Anthony James as Managing Director of the company, a mining engineer with senior underground operational and development experience. He will replace current MD Alex Molyneaux who will remain a director of the company.

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.

Perenti boosts Botswana portfolio with Sandfire Motheo copper project contract

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Perenti Global Ltd says its surface mining business in Africa, African Mining Services (AMS), has been awarded the contract for open-pit mining services at Sandfire Resources’ Motheo copper project in Ghanzi, Botswana.

The contract, which is yet to be finalised, has an estimated value of $496 million over an initial seven-year-and-three-month term with a provision for a one-year extension.

Under the terms of the Mining Services Contract, AMS will identify a suitable local Botswana company or companies as a joint venture partner for the project and transition to the joint venture before the commencement of mining in early 2022.

Finalisation of the contract is contingent on the satisfaction of two primary conditions, namely Sandfire being granted a mining licence for the project; and finalising the terms of the Mining Services Contract.

Perenti Managing Director and Chief Executive Officer, Mark Norwell, said Motheo represented a game-changing growth opportunity for AMS and will substantially increase Perenti’s presence in Botswana.

“Growing our footprint in Botswana is aligned with our 2025 strategy, to further expand into stable mining jurisdictions and pursue quality projects. The benefit of adding Motheo to the Perenti project portfolio is the opportunity to leverage our existing in-region operational presence at Zone 5 (owned by Khoemacau Copper Mining) as well as partnering with Sandfire to develop Botswana’s next large-scale, highly productive, world-class copper mine.

“The Motheo project is another positive step in the ongoing transformation of our AMS business as we seek to create value and certainty for our client Sandfire and the Ghanzi community.”

Motheo is in the Kalahari Copper Belt, an emerging and relatively underexplored copper producing region. It is around 200 km to the southwest of the Khoemacau Zone 5 project, where Perenti, through its subsidiary Barminco, is currently engaged to undertake underground mine development works.

Motheo is held through Sandfire’s subsidiary, Tshukudu Metals, and was approved for development by Sandfire’s Board of Directors in December 2020 following completion of a definitive feasibility study (DFS) on a base case of a 3.2 Mt/y operation with expansion potential.

The DFS outlined an initial 12.5-year operation, underpinned by an updated ore reserve of 39.9 Mt at 0.9% Cu and 12.2 g/t Ag for 360,000 t of contained copper and 15.6 Moz of contained silver, producing on average circa-30,000 t/y of contained copper and 1.2 Moz/y of contained silver over the first 10 years of operations.

Perenti Mining Chief Executive Officer, Paul Muller, said: “Through this commitment and the establishment of a local joint venture partnership, we expect that more than 95% of the workforce will be citizens of Botswana. Furthermore, and leveraging our existing Maun based state-of-the-art mining training centre, our workforce will have access to the latest mining techniques and technology to enable the creation of a safe, highly skilled and productive workforce to support economic growth and diversification within Botswana.”

Muller said the company was also excited by the opportunity to deploy “future-focused mining technology initiatives” on the project that not only provide expected productivity and safety benefits to Sandfire but are also aligned with the two firms’ sustainability goals.

Perenti anticipates pre-production work to commence in late 2021 with mining to commence in early 2022.

Chrysos Corp’s PhotonAssay tech hits major milestone

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Chrysos Corp has announced that its ground-breaking PhotonAssay technology has now assayed over one million customer samples.

The milestone comes amid accelerating demand for the technology, which has seen the number of samples analysed more than triple in the last six months, the Australia-based company said.

Driven in part by increasing industry focus on safety, sustainability, and sample turnaround time, Chrysos PhotonAssay is competing with the centuries-old fire assay process in the gold assaying market. Chrysos says the technology, which originated out of a CSIRO project, is fast taking over fire assay to be the preferred technology of miners and laboratories seeking a solution to the supply chain and environmental challenges created by traditional gold assaying methods.

Chrysos CEO, Dirk Treasure, explained, “Demand for PhotonAssay has grown over the last year and further accelerated in the last six months as more miners and laboratories have reached the conclusion, through their own due diligence, that PhotonAssay not just meets and exceeds their accuracy and cost requirements, but also overcomes the speed, safety, and environmental challenges inherent in fire assay.”

Recently, Chrysos and Intertek declared a deal to install two PhotonAssay units at Intertek’s new Minerals Global Centre of Excellence in Perth, Western Australia. Chrysos also announced a partnership with MSALABS, a subsidiary of Capital Ltd, to deploy at least six PhotonAssay units across the globe over an 18-month period. Prior to that, the company signed a deal enabling Kirkland Lake Gold to use PhotonAssay for its Fosterville Mine in Bendigo, Victoria.

Hitting samples with high-energy X-rays, PhotonAssay causes excitation of atomic nuclei allowing enhanced analysis of gold, silver and complementary elements in as little as two minutes, Chrysos claims. Importantly, the non-destructive process allows large samples of up to 500 g to be measured and provides a “true” bulk reading independent of the chemical or physical form of the sample.

“The significance of the technology’s ability to analyse large sample sizes is underlined by Novo Resources’ recent announcement that it has signed a multi-year deal for priority access to the two new PhotonAssay units being installed at Intertek’s Centre of Excellence,” Chrysos said. “In finalising the agreement, Novo signalled its belief that PhotonAssay is the ideal technique for analysing the nuggety gold mineralisation at its Beatons Creek operation in Western Australia.”

Dr James Tickner, Chrysos Corp Co-founder and Chief Technology Officer, agreed: “Accurate assaying for coarse gold has always been a challenge, and it’s on difficult deposits where the much larger sample mass of PhotonAssay really delivers. It’s great to see industry recognising this, with Novo Resources committing to run at least 20,000 samples per month through each unit at Intertek’s brand-new facility in Perth. The two PhotonAssay units we’ve just commissioned there will really help Intertek deliver faster, cleaner and more accurate results, not just for Novo, but its other customers as well.”

Another factor driving fast adoption of the technology is Chrysos’ commercial and operating model whereby the company leases, rather than sells, its PhotonAssay units to customers, the company says. This approach not only minimises expenditure by relieving the customer of capital expenditure charges and any service, delivery and maintenance fees, but also reduces ongoing staffing, training and related occupational health, safety and environmental costs.

In return, the leasing model facilitates a recurring revenue stream for Chrysos, which the company has used for research and development and the overall broadening of applicability and accessibility of PhotonAssay for wet samples and other metals such as silver and copper, it says.

Reviewing recent successes and foreshadowing upcoming events, Treasure summarised, “Even with more than A$80 million ($62 million) in contracted revenue and 14 PhotonAssay units either in-use or committed, we remain focused on executing our smart, sustainable growth plans. Market feedback indicates that our disruptive technology is helping customers achieve faster, safer and cleaner business outcomes ‒ and that is the type of value creation Chrysos finds compelling.

“Ultimately, we want our customers, shareholders and community stakeholders to feel as much pride using and engaging with PhotonAssay, as we do when we create and deliver it across the globe.”

Scotgold boosts underground fleet at Cononish with DUX truck

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Scotgold, as it looks to further enhance safe production at its Cononish gold-silver mine in Scotland, has added another DUX underground truck to its fleet.

The second DUX truck at Cononish is a DT-12N, a narrow vein version of the DT-12 produced by DUX that measures 1,625 mm wide, has an 11 t payload and a 6 cu.m capacity. The first DT-12N has been operating at the mine for some time.

In the company’s announcement on June 1, it said the mine has been producing both gold concentrate and gravity separated gold dore, following the resolution of various outstanding technical issues affecting the processing plant earlier in the year. The first shipment of concentrate was made on May 11, 2021, achieving a major milestone for the company. The mine poured first gold back in December 2020.

“We shipped 25 t of concentrate at an average of 182.4 g/t of gold, exceeding the target of 150 g/t, achieving maximum price within the agreed terms within the offtake agreement,” the company said. “Modest amounts of gravity gold dore was also produced and sent to refiners this month for further treatment.”

Scotgold said it is encouraged with the mine and process plant performance, although performance had been intermittent to date.

“On given days throughout April and May, both the mine and process plant have been achieving near design rates of production,” it said. “The company is also pleased with the quality of ore that has been mined and produced through the process plant.”

Scotgold says its focus is to further enhance safe production through consistency and stability of mine and process plant operations in parallel with the opening of multiple faces of ore in the underground mine itself.

“The current limited available number of ore faces does limit our immediate ability to focus on the highest-grade ore zones of the Cononish orebody,” it explained. “Having proved that the mine and processing plant can operate as designed, our focus is on reducing outages through more efficient management of spares and having further redundancy in our mining mobile fleet with the arrival of the second haulage DUX truck.”

This new DUX truck will be complemented by an existing fleet that includes an Epiroc T1D single-boom face drilling rig and Epiroc ST2G Scooptram LHD.

When ramped up, Cononish is expected to average annual gold production of 23,370 oz over a nine-year life of mine.

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

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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

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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

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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

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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

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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.”