Tag Archives: Platreef

Ivanplats to trial Epiroc battery-electric drills and LHDs at Platreef mine

Epiroc says it has won a significant order for battery-electric mining equipment from Ivanplats that will be used to develop its greenfield Platreef mine in South Africa in the “most sustainable and productive manner possible”.

Ivanplats, a subsidiary of Canada-based Ivanhoe Mines, has ordered several Boomer M2 Battery face drill rigs and Scooptram ST14 Battery LHDs (pictured).

These machines will be trialled during the Platreef underground mine’s initial development phase, Epiroc said, adding that Ivanplats has the ambition to use all battery-electric vehicles in its mining fleet at Platreef.

The order exceeds ZAR150 million ($10.2 million) in value and was booked in the June quarter of 2021.

Ivanhoe indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats. The South Africa beneficiaries of the approved broad-based, black economic empowerment structure have a 26% stake in the project, with the remaining 10% owned by a Japanese consortium of ITOCHU Corporation, Japan Oil, Gas and Metals National Corporation, and Japan Gas Corporation.

The Platreef 2020 feasibility study builds on the results of the 2017 feasibility study and is based on an unchanged mineral reserve of 125 Mt at 4.4 g/t 3PGE+Au, project designs for mining, and plant and infrastructure as in the 2017 study; except with an increased production rate from 4 Mt/y to 4.4 Mt/y, in two modules of 2.2 Mt/y, for annual production of more than 500,000 oz of palladium, platinum, rhodium and gold; plus more than 35 MIb of nickel and copper.

The initial plan is to start at a mining rate of 700,000 t/y before scaling up. An updated feasibility study on the plan is expected to be published before the end of the year.

Helena Hedblom, Epiroc’s President and CEO, said it was “encouraging” that Ivanplats is considering going all battery-electric at Platreef.

“Battery-electric equipment is increasingly embraced by mining companies as it provides a healthier work environment, lower total operating costs and higher productivity,” she said. “The technology is now well established, and Epiroc is driving this change toward emissions-free mining.”

Marna Cloete, Ivanhoe Mines’ President and CFO, said: “We want to be at the forefront of utilising battery electric, zero-emission equipment at all of our mining operations. This partnership with Epiroc for emissions-free mining equipment at the Platreef Mine is an important first step towards achieving our net-zero carbon emissions goals while mining metals required for a cleaner environment.”

Boomer M2 Battery face drill rigs and Scooptram ST14 Battery loaders are built in Sweden, and are automation-ready and equipped with Epiroc’s telematics solution Certiq.

The equipment will be delivered early to Platreef in 2022. Epiroc will also provide on-site operator and maintenance training to Ivanplats, it said.

Epiroc intends to offer its complete fleet of underground mining equipment as battery-electric versions by 2025, and its full fleet for surface operations as battery-powered versions by 2030.

Ivanplats eyes Platreef project fast track following Shaft 1 sinking work

An integrated development plan (IDP) on the Platreef palladium, platinum, rhodium, nickel, copper and gold project in South Africa has shown the potential to fast-track the development into production.

Consisting of an updated feasibility study and a preliminary economic assessment, the IDP marks an “important step in our vision of building and operating the world’s next great precious metals mine, together with our local community and Japanese partners”, Ivanhoe Mines Co-Chair, Robert Friedland, said.

Ivanhoe indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats. The South Africa beneficiaries of the approved broad-based, black economic empowerment structure have a 26% stake in the project, with the remaining 10% owned by a Japanese consortium of ITOCHU Corporation, Japan Oil, Gas and Metals National Corporation, and Japan Gas Corporation.

The Platreef 2020 feasibility study builds on the results of the 2017 feasibility study and is based on an unchanged mineral reserve of 125 Mt at 4.4 g/t 3PGE+Au, project designs for mining, and plant and infrastructure as in the 2017 study; except with an increased production rate from 4 Mt/y to 4.4 Mt/y, in two modules of 2.2 Mt/y, for annual production of more than 500,000 oz of palladium, platinum, rhodium and gold; plus more than 35 MIb of nickel and copper.

The 2020 feasibility study includes an updated production schedule based on the current project status, costs and economic assumptions, with the schedule for the latest study driven by the sinking of the project’s second, larger shaft (Shaft 2), where early works have commenced. The 2020 study envisions Shaft 2 equipped for hoisting in 2025, allowing for first concentrate production in the latter half of the year. The initial capital cost for the Platreef 2020 feasibility study is estimated at $1.4 billion.

The Platreef IDP also includes the Platreef 2020 preliminary economic assessment, which is an alternate, phased development plan that fast-tracks Platreef into production. The plan uses the project’s first shaft (Shaft 1) for initial hoisting and mine development, with 825,000 t of annual total rock hoisting capacity, of which 125,000 t is allocated for development rock. The alternate plan envisions building an initial concentrator with a capacity of 770,000 t/y, and could produce first concentrate in mid-2024.

“The recently-completed sinking of Shaft 1 has created the opportunity to access early, high-grade tonnes in this scenario,” the company said. “While the 700,000 t/y initial mine is being operated using Shaft 1, there would be opportunities to refine the timing of subsequent phases of expanded production, which is driven by the sinking of Shaft 2.”

Once completed, two 2.2 Mt/y concentrator modules would be commissioned, and the initial concentrator would be ramped up to its full capacity of 770,000 t/y; increasing the steady-state production to 5.2 Mt/y for annual production of more than 600,000 oz of palladium, platinum, rhodium and gold, plus over 40 million pounds of nickel and copper. The initial capital cost for 700,000 t/y under the Platreef 2020 assessment is estimated at $390 million – substantially lower than the Platreef 2020 feasibility study that requires Shaft 2 for first production.

Detailed engineering has commenced on the mine design, 770,000 t/y concentrator and associated infrastructure for the phased development plan, which will be incorporated into an updated feasibility study in 2021, Ivanhoe said. The Shaft 1 changeover will take place simultaneously in preparation for permanent hoisting by early 2022. The budget for 2021 is $59 million, which includes $10 million for commencement of the construction of the headframe to the collar of Shaft 2.

“The Platreef IDP reflects the first phase of development for the Platreef Mine,” the company said. “It is designed to establish an operating platform to support potential future expansions to 12 Mt/y and beyond, as demonstrated in previous studies, which would position Platreef among the largest platinum-group metals producing mines in the world, producing in excess of 1.1 Moz of palladium, platinum, rhodium and gold per year.”

Friedland said: “The thick and flat-lying nature of the high-grade mineralisation of Platreef’s Flatreef deposit will accommodate the use of mechanised and state-of-the-art, automated mining techniques; allowing us to efficiently and safely bring material to surface to produce precious metals vital to a proliferation of modern technologies.”

Marna Cloete, Ivanhoe’s President and CFO, said approximately 60% of the mine’s tailings will be sent back underground to fill mined-out voids, and the remainder will be treated using sustainable, dry-stacking technology.

Mining zones in the current Platreef mine plan occur at depths ranging from around 700-1,200 m below surface. Once expanded mine production is achieved, primary access to the mine will be by way of a 1,104-m-deep, 10-m-diameter production shaft (Shaft 2). Secondary access to the mine will be via the 996-m-deep, 7.25-m-diameter ventilation shaft (Shaft 1) that recently has been sunk to its final depth. During mine production, both shafts also will serve as ventilation intakes. Three additional ventilation exhaust raises (Ventilation Raise 1, 2, and 3) are planned to achieve steady-state production.

Mining methods included in the studies are longhole stoping and drift-and-fill. Each method will use cemented backfill for maximum ore extraction. The production plans in both the PEA’s initial five-year drift-and-fill mining operation off of Shaft 1 and the larger feasibility study expansion are focused on maximising higher-grade areas, which was achieved through optimisation based on stope locations, stope grades, mining method, and zone productivities. The orebody was targeted to recover around 125 Mt at the highest net smelter return.

The ore will be hauled from the stopes to a series of internal ore passes and fed to the bottom of Shaft 2, where it will be crushed and hoisted to surface.

Comminution and flotation test work has indicated that the optimum grind for beneficiation is 80% passing 75 micrometres. Platreef ore is classified as being ‘hard’ to ‘very hard’ and thus not suitable for semi-autogenous grinding; a multi-stage crushing and ball-milling circuit has been selected as the preferred size reduction route, Ivanhoe said.

Improved flotation performance has been achieved in test work using high-chrome grinding media as opposed to carbon steel media. The inclusion of a split-cleaner flotation circuit configuration, in which the fast-floating fraction is treated in a cleaner circuit separate from the medium- and slow-floating fractions, resulted in improved PGE, copper and nickel recoveries and concentrate grades.

A two-phased development approach was used for the flowsheet design comprising a common three-stage crushing circuit, feeding crushed material to milling-flotation modules. Flotation is followed by a common concentrate thickening, concentrate filtration, tailings disposal and tailings-handling facility. The phased approach allows for increased processing flexibility and introduces process redundancy while allowing for phasing of capital and mine ramp-up, the company said.

To further evaluate optimisation opportunities and confirm additional detail design parameters, a mini pilot plant test work program is proposed and will be undertaken as part of the project implementation phase.

The proposed tailings storage facility (TSF) will be developed as a dry stack TSF with an estimated operating life of 32 years. During this time, some 55.4 Mt of tailings will be stored within the dry stack TSF, with the remainder of the tailings to be used as backfill in the underground mine. The dry stack TSF design also caters for an 8 Mt/y ramp-up in production to be explored in future studies.

The dry stack TSF is compliant in terms of required tonnage profile production split between the backfill requirement and dry stack TSF of 35% on average, but is conservatively designed for 40% of non-ore material reporting to the TSF.

Since the Platreef 2017 FS, a hybrid paddock deposition methodology was proposed; however, Ivanplats has decided to change the TSF deposition methodology from upstream design to dry stacking in the Platreef 2020 studies.

Following a study undertaken by Golder Associates Africa in December 2016, it was concluded that stacked tailings storage facilities are deemed to be safer in that there is no hydraulic deposition, hence the risk will be minimal to flood the surrounding areas with tailings in the unlikely event of a catastrophic failure.

“Stacked tailing storage facilities are more water efficient in that the majority of water in the tailings is captured in the dewatering plant, pumped directly back to the concentrator and re-used within the process,” the company said.

The stacked facility will comprise a starter dam constructed primarily of rock fill, engineered tailings, nominally compacted tailings, and random fill. Tailings will be delivered to the dewatering plant situated at the stacking facility using the same pumping systems from the processing plant. Dried tailings will be delivered to the stacking facility using load and haul transportation with trucks from the dewatering plant.

Aside from the rock fill in the starter dam and drainage elements, which include a return water dam, the facility will be developed using dewatered tailings. The infrastructure will have to be in place upon start-up.

For the Platreef 2020 PEA development scenario, it is envisaged to use the approved rock dump footprint within the immediate Platreef mine and concentrator areas, as a dry stacking tailings facility for the initial 700,000 t/y mine. Golder Associates currently is performing the design work to apply for the relevant licences and/or amendments to the existing authorisations.

Ivanhoe advances Platreef development studies after Moolmans completes sinking

Ivanhoe Mines has announced another milestone at the Platreef platinum group metals project in South Africa, with construction complete at the 996-m level station of Shaft 1.

The achievement, completed well ahead of the contractual schedule, according to Ivanhoe, positions the company to equip Platreef’s initial production shaft, if it chooses to proceed with phased development of the mine on the Northern Limb of South Africa’s Bushveld Complex.

Sinking was carried out by contractor Moolmans, with the project remaining ‘Fall-of-Ground’ incident free since shaft sinking operations began in July 2016, the company said. On top of this, in June 2020, Moolmans and the Platreef team achieved South Africa shaft sinking industry leader status in terms of safety performance, according to Ivanhoe, which owns 64% of the project through Ivanplats.

Ivanhoe’s Co-Chairmen, Robert Friedland and Yufeng “Miles” Sun, said: “Given the flurry of recent transactions in precious metals markets, we are actively exploring a number of options that can help us unlock Platreef’s extraordinary value for the benefit of all Ivanhoe stakeholders.

“After all, Platreef is among this planet’s largest precious metals deposits.”

Platreef now has a completed shaft within a few hundred metres of the initial high-grade mining zone, according to Friedland and Sun.

“We have a mining licence, we have water and we have a team of highly-skilled employees,” they said. “The deposit has enormous quantities of palladium, platinum, rhodium, nickel and copper; and it has more ounces of gold than many leading gold mines.”

They concluded: “Given the current precious metals environment, I am confident that the pending studies will showcase the exceptional economics that one would expect from such a thick, high-grade and flat-lying deposit.”

Ivanhoe is updating the Platreef project’s 2017 definitive feasibility study (DFS) to account for development schedule advancement since 2017 when the DFS was completed, as well as updated costs and refreshed metal prices and foreign exchange assumptions.

The DFS for Platreef covered the first phase of production at an initial mining rate of 4 Mt/y, estimating Platreef’s initial average annual production rate would be 476,000 oz of platinum, palladium, rhodium and gold, plus 21 MIb (9,525 t) of nickel and 13 MIb (5,897 t) of copper.

Concurrently, Ivanhoe is finalising a preliminary economic assessment for the phased development production plan for Platreef. The plan targets significantly lower initial capital to accelerate first production by using Shaft 1 as the mine’s initial production shaft, followed by expansions to the production rate as outlined in the 2017 DFS, Ivanhoe said.

“The re-evaluation is being done in parallel with the ongoing mine development work to access the thick, high-grade, flat-lying Flatreef deposit that was discovered in 2010 and outlined in the Platreef 2017 feasibility study,” it said.

The new auxiliary winder for the 7.25 m diameter Shaft 1, which is scheduled to be delivered to Platreef later this year, will be used to assist in equipping the shaft; and thereafter for logistics, shaft examination and auxiliary functions. The auxiliary winder will provide a second means of ingress and egress from the shaft after removal of the stage winder.

Shaft 1 is around 350 m away from a high-grade area of the Flatreef orebody, planned for bulk-scale, mechanised mining.

Ivanhoe looks to align Platreef mine advance with palladium, rhodium price run

Ivanhoe Mines says it is fast-tracking a feasibility study on a smaller-scale, early-stage development plan at its Platreef palladium, platinum, nickel, copper, gold and rhodium project, in the Bushveld Complex of South Africa.

The move comes as spot prices of palladium and rhodium – two key metals contained in the Platreef ore – have soared in recent months. This has propelled Platreef’s ‘metals-price basket’ to a new, all-time high, Ivanhoe said.

Palladium prices surpassed a record $2,100/oz recently as stricter air-quality rules continue to boost demand for the metal used in vehicle pollution-control devices, while the price of rhodium has surged 32% already this month, attaining a price of more than $8,200/oz – the highest price since it hit more than $10,000/oz in 2008.

Ivanhoe’s plan would accelerate the mine’s first production by using Shaft 1 as the mine’s initial production shaft, followed by expansions to the production rate outlined in the project’s 2017 definitive feasibility study (DFS), it said. Ivanhoe’s smaller-scale mine design would also be optimised to target the highest-grade areas of the mineral resource in close vicinity to Shaft 1.

Platreef’s Shaft 1 currently is at a depth of 957 m below surface. It is scheduled to be completed to a final depth of around 1,000 m by the end of July. Work on Shaft 1’s 950-m-level station (pictured) – the shaft’s third and final station – is expected to be completed in March 2020.

Shaft 1 was previously expected to become the primary ventilation shaft during the project’s initial 4 Mt/y production case, with Shaft 2, around 100 m northeast of Shaft 1, providing primary access to the mining zones.

Platreef has an estimated 26.8 Moz of palladium in indicated resources, and an additional 43 Moz in inferred resources. This is in addition to an estimated 1.8 Moz of rhodium in indicated resources and an additional 3.1 Moz in inferred resources. Both of these are at a 2 g/t 3PE+gold cutoff.

In July 2017, Ivanhoe, which indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats, issued an independent DFS for Platreef covering the first phase of production at an initial mining rate of 4 Mt/y. The DFS estimated Platreef’s initial average annual production rate would be 476,000 oz of platinum, palladium, rhodium and gold, plus 21 MIb (9,525 t) of nickel and 13 MIb (5,897 t) of copper.

Pre-sink of Shaft 2 at Ivanhoe’s Platreef underground project months away

In a review of exploration and development activities in 2018, Ivanhoe Mines has gone into some detail on developments at Shaft 2 at the Platreef PGM-nickel-copper-gold project on the northern limb of South Africa’s Bushveld Complex.

This follows a project update issued just after the Mining Indaba event in February.

Shaft 1, expected to reach its final depth of 982 m below surface in early 2020, will ultimately become the primary ventilation shaft during the project’s initial 4 Mt/y production case, but Shaft 2, around 100 m northeast of Shaft 1, will provide primary access to the mining zones.

Ivanhoe said Shaft 2 will have an internal diameter of 10 m, will be lined with concrete and sunk to a planned, final depth of more than 1,104 m below surface.

It will be equipped with two 40-t rock-hoisting skips capable of hoisting a total of 6 Mt/y of ore – the single largest hoisting capacity at any mine in Africa. The headgear for the permanent hoisting facility was designed by South Africa-based Murray & Roberts Cementation.

Ivanhoe said nine blasts were successfully completed in 2018 enabling the excavation of Shaft 2’s box cut to a depth of approximately 29 m below surface and the construction of the concrete hitch (shaft collar foundation) for the 103-m-tall concrete headgear (preparations pictured here) that will house the shaft’s permanent hoisting facilities and support the shaft collar.

Excavation of the box cut and construction of the hitch foundation is expected to be completed in the June quarter, enabling the beginning of the pre-sink, that will extend 84 m below surface, it said.

In July 2017, Ivanhoe, which indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats, issued an independent, definitive feasibility study (DFS) for Platreef covering the first phase of production at an initial mining rate of 4 Mt/y. The DFS estimated Platreef’s initial, average annual production rate would be 476,000 oz of platinum, palladium, rhodium and gold, plus 21 MIb (9,525 t) of nickel and 13 MIb (5,897 t) of copper.

Ivanplats reports on Platreef PGM-nickel-copper-gold project progress

Following a site visit to the Platreef PGM-nickel-copper-gold asset in South Africa just after this month’s Mining Indaba, Ivanplats has provided an update on progress at the project.

In July 2017, Ivanhoe, which indirectly owns 64% of the Platreef project through its subsidiary, Ivanplats, issued an independent, definitive feasibility study (DFS) for Platreef covering the first phase of production at an initial mining rate of 4 Mt/y. The DFS estimated Platreef’s initial, average annual production rate would be 476,000 oz of platinum, palladium, rhodium and gold, plus 21 MIb (9,525 t) of nickel and 13 MIb (5,897 t) of copper.

In the latest update, Ivanplats said good progress continued to be made on Shaft 1’s 850-m-level station. This is the second of three horizontal mining access stations planned for Shaft 1 at Platreef on the northern limb of the Bushveld Complex.

Platreef said: “The first underground mining access station has been constructed at the 750-m level, following earlier development of a water-pumping station at the 450-m level. The third mining access station will be developed at a mine-working depth of 950 m.”

Shaft 1 is expected to reach its projected, final depth of approximately 980 m below surface, complete with all four of the stations, in early 2020, Ivanplats said. The mining zones in the current Platreef mine plan occur at depths ranging from approximately 700 m to 1,200 m below surface.

Construction also is underway on the concrete foundation for the project’s main production shaft ─ Shaft 2, according to Ivanplats. “This foundation will support the 103-m-tall concrete headgear (headframe) that will house Shaft 2’s permanent hoisting facilities and support the shaft collar,” the company said.

Shaft 2 will have an internal diameter of 10 m and will be equipped with two 40-t rock-hoisting skips with a capacity to hoist a total of 6 Mt/y of ore – the single largest hoisting capacity at any mine in Africa, according to Ivanplats.

The South African beneficiaries of the approved broad-based, black economic empowerment structure have a 26% stake in the Platreef project. The remaining 10% is owned by a Japanese consortium of ITOCHU Corp; Japan Oil, Gas and Metals National Corporation; and Japan Gas Corp.

DRA Global moves from PFS to basic engineering at Kakula copper project

DRA Global has been awarded the contract for basic engineering services on the Kakula mine portion of the wider Kamoa-Kakula project in the Democratic Republic of Congo.

The contract scope includes the basic engineering and design associated with all underground mining infrastructure, the concentrator plant and all supporting surface infrastructure.

Kamoa Copper SA, a joint venture between Ivanhoe Mines, Zijin Mining Group and the Government of the Democratic Republic of Congo, will develop the new copper mine, which is expected to yield an estimated 6 Mt/y in its first phase alone.

The Kakula deposit has been independently ranked as the world’s largest, undeveloped, high yield, high-grade copper discovery, according to DRA, with a resource measuring 174 Mt at an average grade of 5.62% Cu.

DRA’s project delivery relationship with Ivanhoe Mines started on the high-grade platinum-group metals, nickel and copper Platreef project in South Africa. “It was on this project that DRA demonstrated its experienced capability in project delivery which proved to be a key differentiator for the organisation on Kakula,” DRA said.

DRA was contracted to complete the prefeasibility study (PFS) for Kamoa Copper SA, in 2017. In October 2018, DRA was further awarded the contract to deliver a complete basic engineering package. Work began in October and is estimated to conclude by mid-2019.

In addition to the basic engineering, DRA offers continued support on the early works, which includes equipping the main declines with dewatering and conveyor systems, ventilation shafts and associated surface infrastructure.

Alistair Hodgkinson, DRA Executive Vice President, Projects, said: “The team working on this project has gone above and beyond to meet deadlines and exceed client expectations ultimately to ensure that this signature project starts producing as soon as possible.”

Earlier this month, Ivanhoe Mines revealed the prefeasibility study for an initial 6 Mt/y copper mine at Kakula, in addition to an updated preliminary economic assessment combining both Kakula and Kamoa into an 18 Mt/y operation.

Ivanhoe Mines’ Platreef Shaft 1 intersects ‘Flatreef’ PGM deposit

Ivanhoe Mines and sinking contractor Aveng Mining have reached a new milestone at its Platreef PGM-nickel-copper-gold project in South Africa with Shaft 1 now at the top of the ‘Flatreef’ deposit, 780 m below surface.

At the Shaft 1 intersection, the flat-to-gently-dipping deposit is an estimated 26 m thick, making it amenable to the sort of bulk-scale mechanised mining most PGM operators would dream of.

This is the first time Platreef, in the Northern Limb of South Africa’s renowned Bushveld complex, has been intercepted by underground mining activity, according to Ivanhoe Mines.

The mining team has now delivered first ore from the underground mine development to a surface stockpile for metallurgical sampling. “The estimated thickness of the mineralised reef (T1 and T2 mineralised zones) at Shaft 1 is 26 m, with grades of platinum-group metals ranging up to 11 g/t 3PE (platinum, palladium and rhodium) plus gold, as well as significant quantities of nickel and copper,” the company said.

The 26 m intersection is expected to yield some 3,000 t of ore, estimated to contain more than 400 oz of PGMs.

The 750 m station on Shaft 1 will provide initial, underground access to the orebody, enabling mine development to proceed during the construction of Shaft 2 – the mine’s main production shaft.

The mining zones in the current Platreef mine plan occur at depths ranging from approximately 700 m to 1,200 m below surface.

Shaft 1’s 750 m station will also allow access for the first raisebore shaft, which will have an internal diameter of 6 m, to provide ventilation to the underground workings during the mine’s ramp-up phase.

As shaft-sinking advances, two additional shaft stations will be developed at mine-working depths of 850 m and 950 m. Shaft 1 is expected to reach its projected, final depth of 980 m below surface, complete with the stations, in early 2020.

Shaft 2

Excavation of the Shaft 2 box cut to a depth of approximately 29 m below surface is progressing well, according to Ivanhoe.

Completion of the box cut will allow for the construction of the concrete hitch (foundation) for the 103 m-tall concrete headframe that will house the shaft’s permanent hoisting facilities and support the shaft collar.

Shaft 2, around 100 m northeast of Shaft 1, will have an internal diameter of 10 m, will be lined with concrete and sunk to a planned, final depth of 1,104 m below surface. It will be equipped with two 40 t rock-hoisting skips with a capacity to hoist a total of 6 Mt/y of ore. This is the single largest hoisting capacity at any mine in Africa, according to Ivanhoe.

Headgear for the permanent hoisting facility was designed by South Africa-based Murray & Roberts Cementation.

In July 2017, Ivanhoe issued an independent, definitive feasibility study (DFS) for Platreef covering the first phase of production at an initial mining rate of 4 Mt/y. The DFS estimated Platreef’s initial, average annual production rate would be 476,000 oz of platinum, palladium, rhodium and gold, plus 21 MIb (9,525 t) of nickel and 13 MIb (5,897 t) of copper.