Overview
Stage | Production |
Mine Type | Open Pit |
Commodities |
|
Mining Method |
|
Processing |
- Flotation
- Dewatering
- Filter press
|
Production Start | 1968 |
Mine Life | 2047 |
Aitik mine - the world’s most productive open-pit copper mine. In Aitik, ore haulage has been automated to a high degree, which provides conditions for large-scale production while also ensuring a safe workplace with good climate performance.
The mining area consists of Aitik and Salmijärvi open pits.
Boliden AB received an environmental permit for the Liikavaara satellite mine and expects to begin production at the end of 2023 year. |
Source:
p. 10
Company | Interest | Ownership |
Boliden AB
|
100 %
|
Indirect
|
Boliden Mineral AB
(operator)
|
100 %
|
Direct
|
Boliden Mineral AB owns 100 % of the Aitik mine.
Source:
p.17-18
Summary:
The Aitik, Salmijärvi, and Aitik East deposits occur along a largely continuous elongate mineralized trend (the Aitik-Salmijärvi mineralization) stretching approximately 5 km along strike from north to south averaging about 500 m in width.
Host rocks of the mineralization at the Aitik deposit consist mainly of paleo-proterozoic (ca. 1.89 billion years) muscovite schists, biotite gneisses, and amphibole-biotite gneisses of volcanic and volcanoclastic origin, crosscut locally by diorite intrusive units. In places the diorite intrusive make up a significant proportion of the mineralized volume, but typically at lower than average grade. Foliation is well developed in the host rocks, dipping at about 50 degrees to the west. The mineralization is mainly structurally controlled and the main mineralisation; Aitik is delineated by a hangingwall thrust and a footwall shear. Main sulfide minerals in the deposit are chalcopyrite, pyrite and pyrrhotite, with significant accessory minerals including magnetite, molybdenite and sulfates. The entire package has been metamorphosed to amphibolite grade resulting in significant recrystallization and coarsening of both sulfide and silicate minerals. Late granite pegmatite dikes crosscut the mineralized host rocks and are generally weakly mineralized to barren.
Mineralization at the Salmijärvi and Aitik East deposits is very similar in nature to the Aitik deposit, with the exception that host rocks are strongly dominated by amphibole-biotite gneisses and local diorite. Sulphide mineralization in these deposits is dominated by chalcopyrite, pyrite and pyrrhotite, although at typically lower grade than in the Aitik deposit.
About 3 km to the east, on separate and volumetrically smaller mineralized trend, sits the paleoproterozoic Liikavaara Cu-(W-Au) deposit. At Liikavaara the mineralisation is hosted by quartz±tourmaline-calcite veins, calcite veins and aplite dykes that cross-cut biotite-amphibole schists and gneisses, steeply dipping to the west. The mineralisation is mainly chalcopyrite, pyrrhotite and pyrite, accessory minerals are sphalerite, galena, scheelite, molybdenite and magnetite. Liikavaara shows slight enrichments in Au, Ag and Bi.
Source:
p.7,20-21
Summary:
Aitik is a Palaeoproterozoic porphyry Cu-Au-Ag deposit, mined as open pit mine consisting of two active pits: Salmijärvi and Aitik. There are also plans to start a third open pit operation in Liikavaara, a satellite, Palaeoproterozoic Cu-(W-Au) deposit, situated 3 km east of Aitik. The mining in Aitik is commenced at three pushbacks designated S3, N6 and N7. Salmijärvi has one active pushback called SA2.
The ore is mined in two open pits along the same mineral deposit. The main pit is called Aitik and measures 4 km by 1.1 km at the surface, with the deepest point currently at 555 meters from the surface. In 2010, mining commenced in a second pit called Salmijärvi which has currently reached a depth of 285 meters below the surface, with a surface footprint of 0.9 by 0.6 km. The main pit will be expanded in all directions with five new pushbacks. Mining of pushback S3 in the southern part of the main pit started in 2016. Pre-stripping of pushback N7 commenced in 2019 to allow mining to start during 2020. No further expansions are planned for the Salmijärvi pit after the current pushback, which will be depleted during early 2023.
The ore and waste rock are blasted in 15-meter-high benches and are loaded on 300 tons capacity-size trucks by large rope shovels or hydraulic excavators. Ore from the deeper parts of the main pit is fed to one of two in-pit-crushers, while ore from pushbacks near the surface and the Salmijärvi pit is transported to a surface crusher situated between the two pits. Waste rock is separated in the loading process and hauled by trucks to dumps at the surface, where potentially acid-forming waste is dumped separately from non-acid-forming waste.
Holes for blasting are drilled with electric drills from Bucyrus and Atlas Copco. Hole depth: 16-17 m Hole diameter: 311 mm Drill attern: 7x9 m Between 200-300 holes are drilled for each round of blasting. A normal blast round produces around 700 000 tonnes of rock for extraction.
Boosters are loaded into the holes followed by emulsion explosives. Explosives: Emulsion explosives (Kemitti-610) from Forcit, about 1 tonne of explosive is used in each hole.
With the help of shovels from Bucyrus, P&H, Komatsu and wheelloaders from Caterpillar, the blasted rock is loaded on to trucks for further tranportation. The largest trucks, CAT 795F, holds about 313 tonnes. A bucket can hold 45 m³ rock (Komatsu 26 m³). The ore is transported to the crusher and the waste rock to a waste rock dumpsite. The machines are equipped with the positioning system Minestar.
Source:
Source:
- subscription is required.
Processing
- Flotation
- Dewatering
- Filter press
Flow Sheet:
Summary:
The milled ore is sent for concentration through a series of froth flotation stages, namely, rougher, scavenger and four cleaning stages.
The milled ore is classified using a spiral classifier. Mineral separation is done by flotation and a copper concentrate is produced. The copper concentrate is dewatered using thickeners and air pressure filters. The precious metals are reported in the copper concentrate. The copper concentrate is trucked to on-site railway terminal and reloaded for further transport by rail to the Boliden Rönnskär smelter in Skelleftehamn.
The plant produces a final concentrate containing 20-23% copper with gold, silver and molybdenum. Copper recovery is at 85-95% while silver and gold is at 65% and 50%, respectively. Molybdenum is currently not being recovered.
Recoveries & Grades:
Commodity | Parameter | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
Copper
|
Recovery Rate, %
| 90.5 | | | | | | |
Copper
|
Head Grade, %
| 0.2 | 0.22 | 0.24 | 0.25 | 0.29 | 0.28 | 0.22 |
Copper
|
Concentrate Grade, %
| 25.2 | 25.5 | 24.8 | 24.2 | 24.6 | 24.8 | 22.1 |
Gold
|
Recovery Rate, %
| 58.6 | | | | | | |
Gold
|
Head Grade, g/t
| 0.1 | 0.11 | 0.13 | 0.13 | 0.14 | 0.13 | 0.11 |
Silver
|
Recovery Rate, %
| 75.3 | | | | | | |
Silver
|
Head Grade, g/t
| 0.86 | 0.87 | 1.06 | 1.17 | 1.82 | 1.98 | 2.11 |
Production:
Commodity | Product | Units | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 | 2016 |
Copper
|
Metal in concentrate
|
M lbs
| 174 | 176 | 201 | 201 | 219 | 216 | 157 |
Copper
|
Concentrate
|
kt
| 314 | 314 | 368 | 377 | 404 | 394 | 320 |
Gold
|
Metal in concentrate
|
oz
| 78,143 | 83,947 | 100,563 | 98,470 | 101,285 | 93,197 | 68,127 |
Silver
|
Metal in concentrate
|
koz
| 900 | 848 | 1,113 | 1,221 | 1,765 | 1,989 | 1,820 |
Operational Metrics:
Metrics | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 |
Ore tonnes mined
| 43.3 Mt | 40,100 kt | 41,661 kt | | | |
Waste
| 30,472,000 t | 31,438,000 t | | | | |
Total tonnes mined
| 73,768,675 t | 71,602,000 t | | | | |
Tonnes milled
| 43,297 kt | 40,100 kt | 41,661 kt | 40,661 kt | 38,472 kt | 39,045 kt |
Annual processing capacity
| | | 45 Mt | | | |
Reserves at December 31, 2022:
Category | Tonnage | Commodity | Grade |
Proven
|
126,000 kt
|
Copper
|
0.17 %
|
Proven
|
126,000 kt
|
Gold
|
0.08 g/t
|
Proven
|
126,000 kt
|
Silver
|
1 g/t
|
Probable
|
1,005,000 kt
|
Copper
|
0.24 %
|
Probable
|
1,005,000 kt
|
Gold
|
0.17 g/t
|
Probable
|
1,005,000 kt
|
Silver
|
1.3 g/t
|
Proven & Probable
|
1,131 Mt
|
Copper
|
0.23 %
|
Proven & Probable
|
1,131 Mt
|
Gold
|
0.16 g/t
|
Measured
|
154,000 kt
|
Copper
|
0.14 %
|
Measured
|
154,000 kt
|
Gold
|
0.06 g/t
|
Measured
|
154,000 kt
|
Silver
|
0.6 g/t
|
Indicated
|
581,000 kt
|
Copper
|
0.18 %
|
Indicated
|
581,000 kt
|
Gold
|
0.12 g/t
|
Indicated
|
581,000 kt
|
Silver
|
0.9 g/t
|
Inferred
|
412,000 kt
|
Copper
|
0.17 %
|
Inferred
|
412,000 kt
|
Gold
|
0.08 g/t
|
Inferred
|
412,000 kt
|
Silver
|
0.8 g/t
|
Commodity Production Costs:
| Commodity | Units | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 |
C1 cash costs
|
Copper
|
USD
|
1.28 / lb†
|
1.08 / lb†
|
0.65 / lb†
|
0.76 / lb†
|
0.77 / lb†
|
0.82 / lb†
|
† Net of By-Product.
Financials:
| Units | 2022 | 2021 | 2020 | 2019 | 2018 | 2017 |
Capital expenditures
|
M SEK
| 3,131 | 1,653 | 1,823 |
1,985
|
1,576
|
1,534
|
Revenue
|
M SEK
| 7,365 | 7,211 | 6,295 |
5,818
|
6,017
|
5,487
|
Operating Income
|
M SEK
| 3,076 | 3,281 | 2,296 |
2,149
|
2,494
|
2,073
|
Mine Management:
Job Title | Name | Phone | Email | Profile | Ref. Date |
Environmental Manager
|
Åsa Sjöblom
|
0970-729162
|
asa.sjoblom@boliden.com
|
|
Jun 12, 2023
|
General Manager
|
Thomas Sundqvist
|
0970-729011
|
thomas.sundqvist@boliden.com
|
|
Jun 20, 2023
|
Mill Manager
|
Andreas Berggren
|
|
|
|
Jun 20, 2023
|
Mine Manager
|
Patrik Gillerstedt
|
|
|
|
Jun 5, 2023
|
Project Manager
|
Johanna Lundin
|
|
|
|
Jun 5, 2023
|
Technical Services Superintendent
|
Åsa Bergstrand
|
|
|
|
Jun 5, 2023
|
Staff:
Employees | Year |
932
|
2022
|
770
|
2021
|
800
|
2020
|
750
|
2019
|
700
|
2018
|
650
|
2017
|
Corporate Filings & Presentations: