MineGuessr – Björkdal, Sweden: Sheeted Vein Gold Mine in the Skellefte District

Overview & location

From space, Björkdal looks like a compact Scandinavian gold operation: a single open pit in the forest, a plant complex and a multi-cell tailings management facility (TMF) to the north. Over nearly 40 years, the timelapse captures the transition from a shallow open pit with a small TMF to a mature site with a deeper pit, expanded tailings, and mine infrastructure that now supports a primarily underground operation.

Today, Björkdal is a long-life gold mine in one of Europe’s most established mining districts and a good example of how an open-pit start-up can gradually evolve into a predominantly underground business.

Where in the world is Björkdal?

Björkdal sits in Skellefteå municipality, Västerbotten County, about 28 km northwest of Skellefteå and roughly 750 km north of Stockholm – within the broader Boliden / Skellefte mining district. The operation is centred on the main Björkdal gold mine, with satellite deposits including:

• Norrberget – an open-pit project ~6 km east of the main mine, planned to provide high-grade feed later in the life of mine.
• Storheden – a nearby sheeted vein system whose mineralisation style closely mirrors Björkdal’s.

Geology & deposit type

Björkdal is a lode-style, sheeted quartz-vein gold deposit hosted in the upper parts of the Paleoproterozoic Skellefte Group sediments.

Key geological features:

• The gold system is expressed as more than a thousand sub-parallel quartz veins, striking mainly 030°–060° from true north and dipping steeply.
• The deposit has been outlined over roughly 1.8 km of strike, 3.5 km of width and to depths of about 900 m below surface.
• Gold occurs mainly as free gold in quartz, but is also associated with bismuth-telluride minerals, electrum and minor sulphides (pyrite, pyrrhotite, marcasite, chalcopyrite). Scheelite and bismuth-tellurides are excellent visual indicators of mineralisation.
• Veins are hosted in a structurally complex environment dominated by the Björkdal shear and related brittle–ductile structures; internal mine terminology even distinguishes “clean” quartz veins from more inclusion-rich “dirty” veins with better gold potential.

For MineGuessr, Björkdal represents the sheeted-vein end of our portfolio, contrasting nicely with the porphyry and massive sulphide systems in other doors of the calendar.

What the mining satellite timelapse shows

The mining satellite timelapse for Björkdal (1984–2022) compresses nearly four decades of development into a few seconds. It gives a visual summary of the mine’s history, which – in production terms – began in 1988 and has since delivered more than 1.6 million ounces of gold.

1. Late 1980s–1990s – open pit growth and high grades
   • Start-up: Ore mining started in July 1988 after discovery in 1983 and feasibility in 1987.
   • Production/grade: Early years achieved feed grades of 2.3–3.3 g/t Au with ~150–1,300 kt of annual mill feed and recoveries near 90%.

   What you see from space:

   • A new open pit rapidly expanding in the surrounding forest.
   • The plant area taking shape next to the pit.
   • The first tailings impoundment cell starting to fill as throughput grows.
2. 2000s – restart, underground development and plant upgrades
   • There was a brief production gap in 2000, followed by a restart in 2001 under new ownership.
   • During the 2000s, grades dropped into roughly the 0.6–1.3 g/t Au range as mining moved through different pit phases, but annual tonnages remained around 1.1–1.2 Mt.
   • Underground mining ramped up from 2008, complementing the open pit and feeding a plant that was progressively upgraded (gravity circuits, additional flotation capacity, process control systems).

   In the timelapse:

   • The main pit continues to push back and deepen.
   • The TMF to the north is expanded and raised in several stages.
   • The site footprint becomes more structured, with internal roads and stockpiles clearly visible.
3. 2010s – stable tonnage, higher underground contribution
   • Through the 2010s, Björkdal typically milled ~1.2–1.3 Mt/year at 1.2–1.7 g/t Au, with overall recoveries around 88–89%.
   • A major step-change was the 2017 flotation expansion, designed to improve recovery at higher throughputs.
   • In July 2019, open-pit mining was suspended, with strategy shifting to focus on higher-margin underground ore and existing low-grade stockpiles.

   In the timelapse:

   • You’ll notice that pit expansion slows and then stabilises around the end of the decade.
   • The TMF continues to grow, with new dam segments and raises clearly visible.
   • Surface changes are more about tailings and infrastructure optimisation than fresh disturbance.
4. 2020s – underground-only production and long-life potential
   • By 2024, Björkdal was sourcing about 82% of mill feed from underground and the remaining 18% from low-grade stockpiles.
   • Total 2024 mill feed was ~1.37 Mt at 1.08 g/t Au, with about 85% recovery and production of ~40,800 oz Au in saleable concentrate.
   • Since 1989, the plant has processed more than 39 Mt of ore and produced roughly 1.66 Moz Au.
   • The current life-of-mine plan includes future open-pit phases (Björkdal Main Pit extension and Norrberget open pit) and progressive use of stockpiles to maintain a ~1.4 Mtpa throughput.

   From a MineGuessr lens, the modern frames show a mature open pit with no recent expansion, a well-defined portal and underground infrastructure, and a multi-cell TMF that is the real indicator of cumulative tonnage moved.

Mining method & processing – how the ore moves

Björkdal is currently a truck-and-scoop underground operation with integrated stockpile re-handling:

• Underground mining: Longhole stoping in a sheeted vein system with ramps, sublevels and cross-cuts perpendicular to vein sets. Development and stopes are mined with modern trackless equipment.
• Processing:
  • Three-stage crushing followed by primary and secondary grinding.
  • A series of gravity concentration steps and flotation producing multiple gravity concentrates plus a sulphide concentrate.
  • Plant capacity: ~3,850 tpd; currently operating around 3,750 tpd.
• Products and logistics:
  • Gravity gold concentrates trucked to Skellefteå and shipped to European smelters.
  • Flotation concentrate trucked to Boliden’s Rönnskär smelter.

Role in the raw materials value chain and energy transition

Björkdal is a gold-only operation in a region better known for base-metal VMS deposits. Its contribution to the raw materials value chain is twofold:

• It provides European gold supply from a long-established Nordic mining district, supporting:
  • High-reliability electronics and connectors
  • Aerospace and medical devices
  • Financial and reserve assets where gold’s role is more macro-economic than “energy transition” specific.
• It showcases how a brownfield site can be kept in production for decades through exploration, underground expansion and plant optimisation rather than simply pushing the pit ever wider.

While gold is not a classic “battery metal”, the Björkdal story is still relevant for energy transition discussions: secure domestic supply, long-term land use, tailings management, and the decarbonisation of energy-intensive underground mines.

What to look for in the MineGuessr timelapse

As a MineGuessr player, could you spot the following:

1. The early growth of the open pit from the late 1980s, cutting into forest and creating the initial bench structure.
2. Progressive tailings dam raises and new cells in the TMF to the north as cumulative throughput climbs.
3. The plateau in pit size from 2019 onward, reflecting the shift to underground-only operations.
4. The relatively compact overall footprint compared with some of the very large open pits elsewhere in the MineGuessr mining advent calendar.

MineGuessr perspective – why this mine was included

We selected Björkdal for the MineGuessr mining advent calendar because it:

• Highlights a sheeted-vein gold system in the Skellefte district, contrasting with the porphyry, iron ore and industrial mineral operations featured on other days.
• Shows a clear life-of-mine evolution in the satellite timelapse – from a growing open pit to a steady-state footprint supported by underground mining and TMF optimisation.
• Represents the Nordic mining model: long-term operation, incremental expansion, and ongoing exploration (Storheden, Norrberget and regional targets) to underpin future feed.

In our GeoGuessr-style mine guessing game, Björkdal helps spark conversations about sheeted-vein gold deposits, open-pit to underground transitions, and tailings management in a mature European jurisdiction.

In December, continue opening a new door every day and you can explore all 24 mines featured this year on the main MineGuessr mining advent calendar page.

• Day 1 - Aitik (Sweden, copper-gold open pit)
  A large, low-grade copper operation south of Gällivare
  👉 Open Door 1 - Aitik
• Day 3 - Kemi (Finland, chrome)
  Chrome mine in northern Finland, Europe’s only chromite operation.
  👉 Open Door 3 - Kemi
• Day 4 - Ørtfjell (Norway, iron ore)
  Iron ore mine in Norway’s Dunderland Valley, evolving from large open pits to underground mining.
  👉 Open Door 4 - Ørtfjell
• Day 5 - Trimouns (France, talc)
  World’s largest working talc quarry high in the French Pyrenees above Luzenac.
  👉 Open Door 5 - Trimouns
• Day 6 - Skouries (Greece, copper-gold porphyry)
  High-grade copper–gold porphyry project in the forests of Halkidiki, still under construction.
  👉 Open Door 6 - Skouries
• Day 7 - Las Cruces (Spain, copper)
  High-grade hydromet copper mine in the Iberian Pyrite Belt north-west of Seville.
  👉 Open Door 7 - Las Cruces
• Day 8 - Assarel–Medet (Bulgaria, copper)
  Twin porphyry copper open pits in the Panagyurishte district, from Europe’s former largest open-pit copper mine at Medet to today’s modern Assarel operation.
  👉 Open Door 8 - Assarel–Medet
• Day 9 - Glomel (France, andalusite)
  World-class andalusite open-pit quarry in Brittany’s Montagnes Noires, supplying refractory minerals for Europe’s steel, foundry, cement and glass industries.
  👉 Open Door 9 - Glomel
• Day 10 - Parnassos–Ghiona (Greece, bauxite)
  Karst-type bauxite mines in the Parnassos–Ghiona mountains, a historic alumina feedstock district supplying Greece’s aluminium industry.
  👉 Open Door 10 - Parnassos–Ghiona
• Day 11 - Kittilä (Finland, gold)
  Europe’s largest primary gold mine at the Suurikuusikko orogenic gold deposit north of the Arctic Circle.
  👉 Open Door 11 - Kittilä
• Day 12 - Oltenia Energy Complex (Romania, lignite)
  Cluster of large open-pit lignite mines and mine-mouth power plants in Gorj County, now at the centre of Romania’s coal phase-out and just transition plans.
  👉 Open Door 12 - Oltenia Energy Complex
• Day 13 - Cornwall china clay (UK)
  Historic Imerys china clay pits near St Austell, where bright white kaolin benches and tips reshape “Clay Country” over decades of mining and restoration.
  👉 Open Door 13 - Cornwall china clay
• Day 14 - Aggeria–Agia Irini (Greece, bentonite)
  Overlapping bentonite open pits on the volcanic island of Milos, anchoring one of Europe’s key industrial minerals districts.
  👉 Open Door 14 - Aggeria–Agia Irini
• Day 15 - Skouriotissa (Cyprus, copper & hydromet)
  Ancient copper mining district in the Troodos ophiolite, now a hydrometallurgical hub processing copper, gold and battery-metal feed.
  👉 Open Door 15 - Skouriotissa
• Day 16 - Tunstead (UK, limestone & cement)
  The UK’s largest limestone quarry near Buxton, feeding an integrated lime and cement works with long-term restoration and biodiversity plans.
  👉 Open Door 16 - Tunstead
• Day 17 - Narva (Estonia, oil shale)
  Large open-pit oil shale mine in Ida-Viru County, supplying the Narva power plants and reshaping the landscape with strip mining and reclamation.
  👉 Open Door 17 - Narva
• Day 18 - Sydvaranger (Norway, iron ore)
  Arctic banded iron formation at Bjørnevatn near Kirkenes, evolving toward DR-grade magnetite for Europe’s green steel transition.
  👉 Open Door 18 - Sydvaranger
• Day 19 - Kevitsa (Finland, nickel–copper–PGE)
  Multimetal open-pit mine in Finnish Lapland, combining Ni–Cu–PGE production with trolley-assisted haulage for lower-emission mining.
  👉 Open Door 19 - Kevitsa
• Day 20 - Styrian Erzberg (Austria, iron ore)
  Terraced “pyramid” open-pit iron ore mine at Eisenerz, turning 12 Mt of rock into ~3 Mt of ore each year for Austria’s steel industry.
  👉 Open Door 20 - Styrian Erzberg
• Day 21 - Minas de Alquife (Spain, iron ore)
  Europe’s largest open-pit iron ore mine in Granada, restarting in 2020 after two decades of closure to supply high-grade ore to European steelmakers.
  👉 Open Door 21 - Minas de Alquife
• Day 22 - Siilinjärvi (Finland, phosphate)
  EU’s only operating phosphate mine in central Finland, mining an Archean carbonatite for fertiliser-grade apatite and creating distinctive pale tailings and phosphogypsum stacks.
  👉 Open Door 22 - Siilinjärvi
• Day 23 - Tellnes (Norway, ilmenite/titanium)
  World-class ilmenite open pit in the Rogaland Anorthosite Province, supplying TiO₂ pigment feedstock from one of Europe’s largest titanium deposits.
  👉 Open Door 23 - Tellnes
• Day 24 - Elatsite (Bulgaria, copper–gold porphyry)
  High-altitude porphyry copper–gold open pit in Bulgaria’s Srednogorie zone, with ore conveyed under the Balkan Mountains to a separate flotation–tailings complex.
  👉 Open Door 24 - Elatsite

About Gosselin Mining

At Gosselin Mining, we work with exactly the kind of operations that Björkdal illustrates so well: long-life, vein-hosted gold deposits where value comes from detailed geology, disciplined cut-off strategies, and careful planning of open-pit/underground transitions and tailings capacity. If you need help to:

• Stress-test your own life-of-mine plan for a low- to medium-grade gold deposit
• Optimise underground vs. open-pit sequencing
• Benchmark your processing performance or ESG profile against peer operations in the Nordics

…you’re very welcome to contact us with us.

Further Reading and References

1. Alkane Resources Ltd (online) Björkdal. Available at https://alkres.com/projects/bjorkdal/ (Accessed on 3 December 2025)