Tag Archives: heap leach

Fortuna keeps Lindero on track for first gold pour in early October

Mine operation news, Mineral project development, Precious metals, , , , , , , , ,

Fortuna Silver Mines says it has started the irrigation and leaching of ore placed on the heap leach pad at the Lindero gold project, in Salta Province, Argentina.

This is ahead of the first gold pour, expected in early October.

Jorge A Ganoza, President, CEO and Director, said: “In spite of all the restrictions and challenges brought by the COVID-19 pandemic, we are managing to successfully advance Lindero in a safe and secure manner for our personnel and neighbours.

“With the start of irrigation, we achieved one more key milestone in the pre-production phase as we prepare for what follows, the first gold pour at our third producing mine.”

Back in July, Fortuna said it had completed the primary and secondary crushing circuits at Lindero and it had started stacking ore on the heap leach pad.

The night shift operations at the primary and secondary crushing circuits began in mid-August and, at month’s end, daily throughput peaked at 17,400 t/d or 93% of design capacity of 18,750 t/d, Fortuna said.

This has seen 277,000 tonnes of ore averaging 0.87 g/t Au, containing an estimated 7,750 oz of gold, placed on the leach pad as of August 31.

Meanwhile, irrigation and leaching of ore on the leach pad commenced on September 1. The company also noted that pre-commissioning of the ADR (adsorption, desorption and regeneration) plant was 80% complete.

GBM earns 50% stake in White Dam through SART plant delivery

Base metals, Metallurgy, Mine operation news, Mining equipment, Mining mergers and acquisitions, Mining services, Precious metals, Water management, , , , , , , , , , ,

Having completed the construction of the SART plant at the White Dam gold-copper heap leach asset in South Australia, GBM Resources has earned a 50% stake in the joint venture operation.

The execution of the joint venture between GBM and Round Oak Minerals, signed on December 18, 2019, was conditional on the completion of the sulphidisation, acidification, recycling and thickening (SART) plant at White Dam.

The SART plant construction was completed broadly as planned, with only slight COVID-19 related delays to delivery times of some key equipment, GBM noted. Staged commissioning activities commenced over the past three weeks as circuits in the plant were progressively completed.

The circuit has also now been continuously operated, with reagent additions and first copper sulphide concentrate having been produced, according to GBM. The gold leaching circuit and SART plant are targeted to reach steady-state operations during the current quarter.

Key contractors contributing to the design and construction of the SART plant include Core Metallurgy (metallurgical test work and process design), ammjohncm (civil and electrical design), Environmental Construction (civil construction) and DKM Electrical (electrical).

GBM also expects to complete a JORC 2012 compliant mineral resource estimate for White Dam shortly, which is expected to identify additional production potential of the existing heap leach operation moving forward, it said.

Peter Rohner, Managing Director and CEO, said: “I would like to thank the Round Oak team, both for their efficiency in finalising the joint venture documentation and, in particular, the efforts of their team on site in constructing the SART plant. I would also like to thank the other contractors involved in completing the construction work in a safe and timely manner.

“We are now working to finalise commissioning and look forward to shipping the first copper concentrates and recovering additional gold bullion in the current quarter.

“The SART plant project at White Dam is not only expected to generate cashflow for GBM, but also to extend the life of the operation and deliver an improved outcome for ultimate project closure by removing copper from the existing heaps.”

White Dam is around 50 km southwest of Broken Hill. It is a heap leach operation that, since 2010, has produced about 175,000 oz of gold from heap leaching of 7.5 Mt of ore at 0.94 g/t Au (which was mined from two open pits).

Fortuna starts stacking at Lindero heap leach gold mine

Bulk handling, Comminution of minerals, Mineral processing, Mineral project development, Precious metals, , , , , , ,

Fortuna Silver Mines has completed the primary and secondary crushing circuits at the Lindero gold project, in Salta Province, Argentina, with the company starting to stack ore on the heap leach pad.

As of the end of June, the overall project is now 97% complete, with the first gold pour expected at the end of the September quarter, Fortuna said.

Jorge A Ganoza, President, CEO and Director of Fortuna, said: “The successful commissioning of the primary and secondary crushing circuits and the start of stacking ore on the heap leach pad are key and much awaited milestones at Lindero. Our project team is delivering on schedule and budget according to the revised plan, despite the challenges and limitations of carrying on construction activities under COVID-19 related constraints.

“The next upcoming milestone is the start of heap irrigation which is scheduled for the end of August.”

The ramp-up phase of the primary and secondary crushing circuits will involve an increase in production until nominal rates of 18,750 t/d are achieved, the company said. Fortuna expects to achieve nominal rate production in the December quarter of 2020, inclusive of the tertiary high pressure grinding roll system and agglomeration plant.

Ore for the commissioning and initial ramp-up of the crushing circuit and stacking on the heap leach pad is being sourced from the medium-grade coarse ore stockpile inventory of around 1 Mt averaging 0.55 g/t Au.

During the period from July to December, an estimated 1.7-1.9 Mt of ore is scheduled to be placed on the leach pad with an average gold grade of 1-1.1 g/t, the company said. The estimated stripping ratio during this period is 0.68-0.75.

Final construction activities related to the process ponds, ADR (adsorption, desorption and regeneration) and SART (sulphidisation, acidification, recycling and thickening) plants continues with electrical and piping installations progressing according to plan, Fortuna said. The process pond and ADR plant electric rooms have been energised, with pre-commissioning of the solution handling system commencing on July 11 with the barren pond pumping equipment.

Lindero has been designed as an 18,750 t/d owner-operated open-pit mine with a pit life of 13 years based on current mineral reserves.

Rio2 and STRACON establish mining and construction alliance for Fenix gold project

Mineral project development, Mining services, Precious metals, , , , , , , , , , , ,

Rio2 Ltd says it has taken another key step towards the development of its Fenix gold project, in Chile, by selecting STRACON SA as the lead mining services contractor for the project.

Both companies have executed an early contractor involvement (ECI) agreement for early works associated with contract mining services. Under the ECI agreement, the parties will work exclusively over the coming months to further optimise the mining and civil construction aspects of the project and conclude contract documentation.

The scope of the mining services contract will include mining of ore at the rate of 7.3 Mt/y (20,000 t/d), waste mining, drilling, blasting, hauling, supply of operating personnel and mining equipment, supervision and management, dust suppression and road maintenance. The scope also includes water transportation from Copiapó to the mine site and maintenance of the entire mobile fleet of equipment plus all pre-mining and civil construction activities including the construction of platforms, leach pad, ponds, access roads and waste material deposits.

The financial terms of the mining contract will use an alliancing-style commercial framework based on the mine plan, methodologies and productivity estimate assumptions contained in the prefeasibility study, which outlined a heap leach gold mine producing an average of 93,000 oz/y during the first 13 years and 50,000 oz/y during the final three years of production as stockpiled ore is being crushed and leached.

The environmental baseline study for the Environmental Impact Assessment (EIA) of the Fenix gold project has been progressing since November 2018. During 2019, engineering works and studies were completed for inclusion in the EIA. In January 2020, the information gathering stage for the baseline study was finalised, with the EIA completed and filed with the Environmental Impact Assessment System in the March quarter. Environmental approval is expected in the June quarter of 2021.

The preparation of sectorial permit applications is currently in process and will be submitted in conjunction with the filing of the EIA. The approval of sectorial permits is expected in the September quarter of 2021 and the start of earthworks for construction of the project is targeted for the December quarter of 2021.

The basis for Rio2 establishing a mining and construction alliance with STRACON at the Fenix gold project is a best for project business strategy, the company said. Together with STRACON, the Rio2 management team collaborated, implemented and executed with this same approach when they built and operated the La Arena and Shahuindo gold mines in Peru with Rio Alto Mining.

At Fenix, Rio2 and STRACON will work together as an integrated team, dedicated to exceeding goals, controlling budgets and adding value through exceptional performance while working in a safe and environmentally sustainable manner focused on every detail of the mining and construction process, Rio2 said.

“The alliance will implement an inclusive social policy as a priority based on the hiring of local personnel and service companies from Copiapó and the Atacama Region,” it added.

The payment model of an alliance includes reimbursement of 100% of contractor project costs plus a fee (corporate overheads and profit); a key performance indicator-based regime that rewards for outstanding performance and punishes poor performance; and unanimous, best for project, management and decision making and the selection of an integrated owner/contractor team on the basis of best person for each position and avoiding duplication of roles, Rio 2 said.

Alex Black, President and CEO of Rio2, said: “The signing of this ECI agreement with STRACON, a leading mining and civil construction contractor in Latin America, forms a key part of Rio2’s strategy to prepare for next year’s construction phase of our Fenix gold project.

“The Rio2 management team is pleased to work again with STRACON, this time in Chile, and look forward to further optimising the mining and construction solution for the project and finalising contract documentation in readiness for next year’s work program.”

Steve Dixon, Chief Executive Officer of STRACON, said: “The project will be delivered under a collaborative alliance agreement, a framework which has been successfully utilised over the past 10 years at several of STRACON’s projects throughout Latin America.”

Alio Gold looks to new loading and hauling equipment for production boost

Equipment maintenance, Mine operation news, Mining equipment, Mining services, Precious metals, , , , , , , , ,

Alio Gold has signed lease agreements for the acquisition of new loading and hauling equipment at the Florida Canyon mine, in Nevada, USA.

The fleet is comprised of thirteen 90-t haul trucks and three matched wheel loaders, Alio said.

On top of this, a maintenance and services contract has been signed that provides guaranteed mechanical availability of the new fleet and encompasses all required maintenance activities over the life of the lease agreement, according to the company.

Both agreements are for approximately five years, depending on the actual hours of operation, after which the equipment can be purchased for some $2 million, Alio said, adding that the existing fleet will be retired as the new fleet becomes operational.

“Florida Canyon is well advanced on commissioning the new fleet with four trucks and one loader currently production ready; five additional trucks and one loader are currently on site in various stages of assembly; and the remaining four trucks and loader are due for delivery in October,” the company said.

Alio acquired the Florida Canyon gold mine during a business combination transaction with Rye Patch Gold in 2018. The heap leach operation produced 47,353 oz of gold and 31,993 oz of silver in 2018.

Mark Backens, President and CEO of Alio Gold, said acquiring the new loading and haulage fleet removed the primary cause for the underperformance of the mine.

“With availability now guaranteed, we will be better able to achieve our production objectives,” he said. “Once the fleet is fully operational in November, we expect to see increased ore movement leading to higher gold production and lower cash costs. We look forward to providing the market additional guidance for 2020 once the new equipment is fully operational.”

In addition, Florida Canyon has received all required permits to initiate construction of the second heap leach pad. Contractor mobilisation has commenced, and long lead-time items have been ordered. Construction is expected to take around six months and could be completed in stages to facilitate early placement and leaching of ore.

“Receipt of the construction permit for the second phase of the leach pads is a major milestone for Florida Canyon and positions the company nicely for increased profitable production in 2020,” Backens added.

First gold poured at Victoria’s Eagle mine in Yukon

Mine operation news, Mineral project development, Precious metals, , , , , ,

Victoria Gold Corp has achieved its first gold pour at the Eagle mine in the Yukon, Canada.

The inaugural gold bar was poured by Sandy Silver, Yukon’s Premier, and weighed in at 1,001 oz, the company said.

John McConnell, President & CEO of Victoria Gold, said: “After all the blood, sweat and tears required to explore, develop, permit, finance and build a gold mine in Canada’s north, it is extremely gratifying to pour the first gold bar at Eagle.

“With this key milestone behind us, we are focused on building ore on the heap leach pad and exceeding expectations for all our stakeholders.”

Ramp-up of operations at site continues to proceed and the company said it was exceeding the ramp up schedule for ore mined and ore tonnes placed on the heap leach pad.

Eagle was expected to cost C$487 million ($367 million) to build and has the potential to produce around 200,000 oz/y from a mine operating at 33,700 t/d. The operation will produce doré from a conventional open-pit with a three-stage crushing plant, in-valley heap leach and CIL adsorption-desorption gold recovery plant.

Northern Vertex Mining ready for more gold at Moss mine

Metallurgy, Mine operation news, Mineral processing, Precious metals, , , , , , , ,

Production looks like increasing at Northern Vertex Mining’s recently started up Moss gold-silver mine, in Arizona, USA, as recent modifications to the Merrill Crowe facility and additional output from the heap leach kick in.

The company produced 7,482 oz of gold and 45,876 oz of silver during the three months to the end of June, compared with 6,057 oz of gold and 25,558 oz of silver, marking the company’s strongest quarter to date. In June, alone, Northern Vertex saw 2,580 oz of gold and 18,051 oz of silver come out of the operation.

The Moss open pit and heap leach gold and silver mine hit its commercial straps in September 2018, at which point the company said expected fiscal 2019 production guidance was 36,000-40,000 oz of gold equivalent production.

Northern Vertex said this week that its operations team has made progress in correcting issues that have hampered the process plant since started up, with modifications to the filter press piping, clarifiers and vacuum pump system nearing completion.

“We have observed a large decrease in reagent consumption and an immediate improvement in recoveries of gold and silver from the pregnant solutions,” the company said.

Such improvements to the Merrill Crowe facility recently resulted in the company’s single largest gold shipment to date – of $1.2 million representing nine days of production.

The Moss team initiated a recovery study of the heap leach pad in May 2019, with the purpose to confirm consistent moisture percolation throughout the pad; measure solution volume and solution grade retained in various areas (panels) of the pad, in order to determine the gold and silver inventory remaining on the pad; obtain samples for further bottle roll testing, in order to estimate the amount of gold inventory that can be recovered by re-leach; and design and implement a leach solution application plan to recover additional gold from the leach pad inventory.

Results from the first panel (known as the ‘Central Panel’), which contains approximately 235,000 t of ore have been received, the company said. “Results show remarkable consistency in the percolation of solution, both laterally and vertically. Furthermore, the study confirms there are no dry areas, channelling is not occurring, the pad is retaining its moisture as expected and that the recoverable gold and silver in inventory will meet or exceed feasibility predicted recoveries.”

While the full study, which will include an additional five panels is ongoing, Jim Gubler, Process Manager at Northern Vertex, said the results from the Central Panel indicated there are around 5,000 oz of recoverable gold contained in this area, of which an “estimated 3,000 oz have already been dissolved in the water held in the heap and need only to be flushed and collected”.

He added: “With the leach solution application plan that we have designed, we are projecting that a significant portion of this gold will be recovered over the next several months, which should add to our normal monthly production.”

The ongoing column test program (using crushed ore samples) is predicting ultimate recoveries of approximately 80% for gold and 60% for silver from the heap leach. The column test work on the crusher samples and the heap leach pad recovery study described above will also be used to optimise and shorten the recovery curves going forward, using live ore panels for testing rather than bulk samples that were used in the feasibility, Northern Vertex said.

“Every current test being run indicates that we should be able to outperform the feasibility recovery curves,” the company concluded.

Wood and Cementation Americas complete Terra Nova Technologies deal

Bulk handling, Comminution of minerals, Mineral processing, Mining equipment, Mining mergers and acquisitions, Mining services, Water management, , , , , , , , ,

Wood says it has completed the sale of conveyor systems business Terra Nova Technologies (TNT), close to six weeks after the deal was announced.

Following a strategic review of its portfolio, Wood identified potential asset disposals which were expected to generate proceeds in the range of $200-$300 million, with the TNT sale making a “good contribution to the asset disposal program”, it said.

The TNT business was sold to Cementation Americas, a firm owned by Murray & Roberts Holdings Ltd, for $38 million.

Back in late-March when the deal was announced, David Kemp, Wood Chief Financial Officer, said: “Terra Nova Technologies has a strong track record in delivering material handling equipment to our customers. Wood’s strategy going forward is to focus on asset-light solutions rather than the manufacture/fabrication of equipment.”

Cementation Americas said TNT has earned a solid reputation for providing quality design, supply and commissioning services for crushing and screening plants, overland conveyors, heap leach systems and mobile stacking systems for waste and dry tailings.

Justin Oleson, President of Cementation Americas, said at the time: “The purchase of TNT fits well within Cementation’s strategy to improve our ability to serve clients, both geographically and across the mining value chain. The combining of Cementation and TNT complements both our underground and surface design/build portfolios, and better positions Cementation to support our client’s total mining needs.”

Eldorado Gold to spend $520 million on Kisladag mill in Turkey

Metallurgy, Mine operation news, Mineral processing, Precious metals, , , , ,

The board of directors of Eldorado Gold have given the go ahead to build a mill at the Kisladag gold mine in Turkey, as the operation transitions away from its heap leaching roots.

The Mill Project is expected to cost $520 million, including $384 million for the mill, $75 million for pre-stripping, and $61 million in contingency and growth allowance.

Reserves of 3 Moz grading 0.81 g/t Au, accounting for depletion over the first four months of 2018, support a nine-year mine life with average annual production of 270,000 oz of gold at an all in sustaining cost of $793/oz, according to Eldorado.

Production at the Kisladag heap leach operation came in at 34,070 oz in the September quarter, marginally lower year-on-year. No additional ore has been placed on the heap leach pad since April 2018.

The project comes with an estimated after-tax net present value (5% discount rate) of $392 million and a payback period of 3.9 years, all at an assumed gold price of $1,300/oz.

The mill is expected to begin commissioning activities in late 2020, with production expected in the first half of 2021.