| Written by Michal Wozniakowski-Zehenter
Bingham Canyon Mine, United States
Otherwise known as the Kennecott Copper Mine, the Bingham Canyon Mine was the largest example of what could be done with human ingenuity and engineering. This open-pit mine is located in the Oquirrh Mountains of Utah, situated just southwest of Salt Lake City, and has managed to retain a niche in the annals of history as the largest man-made excavation on Earth. Its dimensions are stunning: about 4 kilometres across, plunging over 1.2 kilometres deep, nearly large enough to be viewed from space. Since its beginning in 1906, the mine has extracted over 19 million tons of copper, easily making this one of the most productive mining operations in history. It is owned by the Rio Tinto Group, a British-Australian multinational organisation, and its activities are under the management of Kennecott Utah Copper LLC, a division of Rio Tinto.
However, copper is not the only commodity mined here; the mine has extracted significant quantities of gold, silver, and molybdenum as its valuable by-products. It takes a stunning amount of coordination and technology just to keep the operation moving, with great haul trucks capable of carrying hundreds of tons up and down labyrinthine roads cut into its sides. To spectators at the official observation site, those giant haul trucks look tiny-toy-sized compared to the vast pit surrounding them. Such a long life has not been without its troubles. Events such as the well-documented 2013 massive landslide shifted millions of cubic meters of rock and temporarily halted operations to continue the risks involved in mining at such a scale.
The Bingham Canyon Mine remains an essential part of the U.S. mining industry, symbolising in many ways the ability of the industry not only to adapt but also to innovate. Besides the industrial contribution, the mine has acted as a reminder of the environmental challenges and questions of sustainability that large-scale extraction puts forward when the balance between economic gain and ecological impact is becoming an ever-more critical concern. The success of the mine has also given way to technological advances in excavation, waste management, and ore processing advances that have become the gold standard for operations all over the world.
Chuquicamata Mine, Chile
The Chuquicamata Mine is an open pit copper mine in northern Chile and the second-deepest open pit mine in the world. Nicknamed "Chuqui," it is the most recognisable mining giant in Chile, having been in operation since 1915. It is an underground mine owned and operated by the state-owned copper mining company, Codelco. It forms part of the company's Codelco Norte division, which also includes the Radomiro Tomic (RT) mine located on the same mineralised system. Such strategic integration underlines the magnitude of this mining complex within Chile's economic schema.
The development of Chuquicamata has evolved from purely surface to both surface and underground mining operations. The underground portion of the mine was designed to extract the ore body situated beneath the current open pit mine. Conceptual engineering of the underground mine started in 2007, and the plans were finalised in March 2009. The project received environmental authorisation by September 2010, while the underground mining operations officially started in 2019. This is very important because it extends the life of the mine due to open-pit reserves that will not be easy to reach. In this regard, the mine will continue its production for many more years and remain one of the largest open pit mines in the world.
The mine is 1,650 kilometres north of Santiago and about 15 kilometres north of Calama, nestled in the mineral-rich Antofagasta region in northern Chile. Its prime location is not just geographical but geological as well. The mine is located on the Chuqui Porphyry Complex: a big, elongated intrusive body trending NNE. This is a large, approximately 14-kilometer-long by 1.5-kilometer-wide complex connected with Chuquicamata and RT mines. The complex consists of the East, West, Banco, and Fine Texture Porphyries, hosting steep and near-vertical formations.
Escondida Mine, Chile
The Escondida Mine in northern Chile is considered the world's largest single copper cathode and concentrate producer. Works started during the late 1990s, with a mine life estimated to be 40 years, hence a long-term interest. This mine is co-owned and operated by a consortium of mining giants, with BHP holding 57.5%, Rio Tinto holding 30%, and the remaining 12.5% being held by JECO. Ownership structure thus points to the strategic relevance of Escondida in the portfolio of major group companies as one of the largest open pit mines globally. In November 2021, it undertook an independent assurance process to be awarded the Copper Mark for responsible production in recognition of its commitment to ethical performance. During the first half of 2022, Escondida produced 824.4 kt, 12% higher than the output in the same period in 2021. Strong performance such as this consolidates Escondida's position among the giants of copper production. It also aspires to be sustainable, leveraging the considerable solar and wind resources available to Chile. This move also adheres to the country's Energa 2025 policy, which calls for 20% of its energy sources to be renewable by the year 2025. This pledge toward renewable energy echoes a greater trend within the industry to render mining processes more "green".
Geographically, Escondida is located in the arid expanse of the Atacama Desert, 160 kilometres southeast of the port city of Antofagasta, at an altitude of 3,050 meters above sea level. The mine's geology is connected with three porphyry bodies intruded along the prominent Chilean west fissure fault system, a fact that speaks much about the mineral wealth of the region. The primary hydrothermal sulphide ore, grading between 0.2% and 1% copper, is overlain by a leached cap up to 180 meters thick. This cap overlies high-grade, supergene-enriched ore and primary sulphide mineralisation, which consists of pyrite, chalcopyrite, and bornite with covellite and chalcocite in the enriched zones.
Combined proved and probable ore reserves of Escondida and Escondida Norte in mid-2004 totalled 2,018 mt of copper sulphide ore grading 1.24% total Cu, 1,701 mt of low-grade copper sulphide ore grading 0.55% Cu, and 290 mt of copper oxide ore grading 0.73% acid-soluble Cu.
Production at Escondido has been steadily expanding since the find came online. Early developments in the 1990s and subsequent expansions increased production from 320,000 tpa to 480,000 tpa and then up to 800,000 tpa by 1996. The concentrator was significantly expanded in 1998, increasing capacity to 127,000 t/d of ore. Shortly afterwards, a new oxide ore processing plant started operations and by mid-1999 reached its design rate of 125,000 tpa of electrolytic copper. A further major milestone was the completion in September 2002 of the $1.044 billion Phase 4 concentrator. Additional capacity again utilised internally generated funding.
The opening of the Escondida Norte pit, which is 5 kilometres north of the headframe, was enabled with a US$400 million investment. In 2005, ore from Escondida Norte was trucked to existing treatment facilities after pre-stripping 126 mt of material. Yet another leap forward was the sulphide leach project that started in 2007; it was tailored to produce 180,000 tpa of cathode copper with an $870 million investment.
Mirny Diamond Mine, Russia
An example of the bold industrial ambition of the Soviet Union is the Mirny Diamond Mine, lying in an extremely far-eastern area of the landmass of Russia, particularly in eastern Siberia. It is also simply known as the Mir Mine and is located within the town of Mirny in the Sakha Republic or Yakutia. Mirny is one of the largest open-pit mines and was once the most productive diamond mine. It remains one of the deepest and largest openpit excavations ever created: Measuring 1,200 meters in diameter and 525 meters deep, these proportions are so great that the mine is easily observable from space and has become one of the most identifiable features of the Siberian landscape.
The Mirny Diamond Mine began its story in the mid-1950s, a very urgent time when the Soviet Union was in serious need of new sources to feed its economic boom and provide the blossoming industries and infrastructure with a regular supply of valuable resources. Deposits of kimberlite ore, volcanic rock that may host diamonds, were found by Yuri Khabardin, together with other geologists, in 1955 near the village called Mirny. This find brought a rush of excitement, developing the mine extremely fast. Starting operations just two years later, in 1957, Mirny Mine immediately became very important in the Soviet diamond industry.
During the early years of mining in Mirny, the challenges were really extraordinary. The site's remote location coupled with the extreme Siberian climate made operations grueling for the workforce. Winters are extreme, and temperatures as low as -40°C are common. Such low temperatures create extreme difficulties concerning equipment's operability and employees' safety and efficiency (see also: mine access). The Soviet government invested in heating systems and insulation technologies that enabled activities throughout the year.
At its peak, Mirny Diamond Mine produced an incredible quantity of high-quality diamonds that greatly helped to establish the position of the Soviet Union in the world's diamond market. The production from this mine was so huge that it actually interfered with the world market in diamond prices. The Soviet government immediately recognised the strategic value of this new resource. It kept production figures and all other information about the mine strictly secret, thus building up an atmosphere of mystery concerning this site. As a result, this place turned out to be one of the symbols of Soviet power and an ingenious marvel in mining.
Miners needed ingenious approaches to mine at Mirny due to its gigantic size and depth. The open pit excavation was done in a series of benches carved into the walls of the pit, thus giving it a stepped appearance to maximise stability while still allowing trucks and machinery access to deeper levels of the mine. The open pit method allowed the extraction of immense quantities of kimberlite ore, which had to be transported for treatment to separate the diamonds. Along with the impressive logistics of extracting the mining work, an efficient infrastructure had to be able to treat the ore and immense volumes of material. After some accidents and dramatic moments, the mine was successful. The depth of the pit meant the constant fight with the stability of the walls and the permanent risk of landslides. That, added to cold weather and geological pressure, presented extra obstacles that were carefully managed. As years passed by, and the open-pit mine reached the limits of what could economically be taken from it, plans were made for switching over to underground mining in order to reach deeper deposits. However, the economics of such a transition, coupled with changing global markets and competition, proved to be complex.
In 2001, the Mirny Mine closed its open-pit operations, marking truly the end of an era for this gigantic site. Its legend lives on, though, in tales of how it shaped not only the diamond market but the surrounding region. This mine was to become the reason for the town of Mirny to grow into an industrial hub, also serving as a centre where workers, along with their families, could live. The infrastructural projects, schools, and community services in Mirny were all heavily subsidised by the economic boom that the mine had brought into this region, thus leaving a mark which is still felt today.
Grasberg Mine, Indonesia
The Grasberg Mine in the Papua-Indonesian highlands is one of the most impressive and complex mining centres in the world. As a result of the biggest production of gold and copper, it is one of the largest open-pit mines worldwide. Freeport-McMoRan operates and owns the mine, though the Indonesian government holds a majority stake through Inalum or Indonesia Asahan Aluminium; this mine has been the source of much economic significance and political debate for decades. Grasberg is a vast open-pit mine that runs several kilometers in length and has depths of over 600 meters; it has produced billions of dollars in minerals over its life span and significantly contributed to Indonesia's economy.
The transformation of Grasberg from the moment of its discovery to an industrial powerhouse indeed involved ingenuity, great difficulty, and high strategy. Few mining operations must overcome the logistical and environmental obstacles that go hand in hand with a location deep in the jungles and towering peaks of Papua (see also: mine protection). Reaching the Grasberg is much resembling hard travel-by air first, followed by tortuous, high-altitude roads. Much like the Mirny Mine, which overcame the cruel Siberian climate, Grasberg has its formidable surroundings to which it has had to adapt. Mining at great altitudes has its particular challenges, increased here with heavy rainfall and unstable ground; thus, innovative solutions and robust infrastructure have been in order. Whereas Mirny had to endure icy cold temperatures with sophisticated heating systems, Grasberg has adopted advanced technologies for drainage and slope stabilisation to regulate its tropical environment. These are very important measures in view of the probability of landslides and other geological instabilities common with mining on steep mountainous terrains. Besides the production volume, Grasberg provides an even deeper influence on the local and nationwide economic indicators: the mine employs several thousand employees, providing a huge contribution to the regional economic performance and supporting the local communities. As is typical of towns such as Mirny, which grew around the mining operation at the Mirny Diamond Mine, communities surrounding Grasberg likewise experienced a growth in population and the construction of infrastructure associated with the mine's operation. Very often, the economic benefits from the mine equated to better schools, medical facilities, and other social services for the area.
The geology of Grasberg is just as richly complex as that of Mirny. Both mines have, in their histories, been located in regions where the natural geological processes have favoured mineral accumulations. While Mirny was characteristically defined by its kimberlite pipes and primary diamond formations, Grasberg bears a copper-gold porphyry deposit. The major ore bodies contain substantial copper and gold accumulations within deposits and other intricate formations that require even advanced technologies in extraction and processing. This factor makes the Grasberg complex and challenging to process. The facilities installed within the Grasberg area are competent enough, using ultra-modern technology to ensure effective enrichment and recovery of ores efficiently and effectively.
Udachnaya Pipe, Russia
The Udachnaya Pipe is one of the oldest and most productive diamond mines of the Sakha Republic, Yakutia, Russia, and a testament to the ambitious exploration and mining legacy of the Soviet Union. Being operated by ALROSA, the world's largest diamond mining company, it has been an integral part of its portfolio for decades and has played an important role in over 60 years of ALROSA's diamond exploration, mining, and sales. Open-pit mining began in 1971, and the mine reached its peak production in the early 1990s at more than 12 million tpy, representing more than half of the total rough diamonds produced by ALROSA. The Udachnaya pipe is one of the 10 deepest open-pit mines in the world, being more than 630 meters deep.
The history of the Udachnaya Pipe is inextricably linked with the significant diamond discoveries of the Soviet period. Everything started with the very first Yakut diamond, found in 1949. Five years later, on August 21, 1954, fortune finally smiled when geologists Larisa Popugaeva and Natalya Sarsadskikh discovered the first pipe of kimberlite, Zarnitsa, which signalled ALROSA's entry into the sphere of primary diamond deposits. This discovery was all that was needed to trigger a string of discoveries, including the fabled Mirny Diamond Mine, another imposing site that, just like Udachnaya, had shown the full range of versatility of Siberia's diamond-rich geology. Actually, the Udachnaya Pipe itself dates back to a year after the Zarnitsa discovery, within days of the famous Mirny Mine being discovered. A young Soviet geologist, Vladimir Shchukin, struck luck in the exploration works when he came upon a chunk of metamorphic rock that was to be found just about 2,000 meters deep. Such rock, brought to the surface by kimberlite and known as volcanic conduit bearing, indicated that there was a significant deposit. Early findings by Shchukin were promising. "We found two diamonds in the first two prospecting holes," he later remembered one of them, a perfect octahedron with 4 mm facets. Unlike Zarnitsa, where 200 prospecting holes yielded no diamonds, Udachnaya was a different story altogether. A small sample taken back to the base yielded an astonishing 43 crystals with high grades of about 3 carats per cubic meter, confirming that, indeed, the pipe was massive.
It became one of the most prolific diamond sources in the world, fully earning its reputation over the decades of intensive mining that followed. The success of this open-pit mine underlined not only ALROSA's dominance in the diamond market but also its considerable contribution to the Russian economy. The level of mining, however, brings its own problems, which are very similar to other deep site mining, such as the Mirny Diamond Mine, with similar issues about wall stability and the need for specialised equipment because of the extreme conditions involving winters in Siberia. Such challenges required robust infrastructure and techniques capable of withstanding continuous cold and geological pressure of mining operations for over 600 meters below the surface.
Fimiston Open Pit, Australia
Commonly referred to as the Super Pit, the Fimiston Open Pit is found in Western Australia's Kalgoorlie region, representing the country's largest open pit gold mine. This mine has been a huge epitome of the gold mining industry of this country, measuring 3.5 kilometres in length and 1.5 kilometres in width. It plunges approximately 600 meters in depth. The mine's history reflects significant changes in ownership over the years. The Super Pit is owned by the 50:50 joint venture Kalgoorlie Consolidated Gold Mines until November and January 2020, respectively, operated by Barrick Gold and Newmont Mining. The companies eventually sold their respective interests to Saracen Mineral Holdings and Northern Star Resources in January 2020.
In February 2021, the Saracen Mineral and Northern Star Resources announced a merger of equals; hence, Northern Star Resources became the sole owner of KCGM. Such a merger dissolved the longtime KCGM joint venture in June 2021 and paved a new chapter for the Fimiston Open Pit under a single operation. In full control, Northern Star Resources drew ambitious plans for the future of the mine. The company is currently conducting an A$1.5 billion ($1.01 billion) expansion of the Fimiston processing facility, a major investment it hopes will help modernise and increase output from the mine. Targeted for completion by 2029, the project will increase production capacity at the mine, pushing output to around 900,000 ounces of gold annually.
These ownership transitions and investments mark the continued evolution of the Super Pit, which testifies to the strategic importance of sustaining and expanding one of Australia's most productive mining sites. The status of the mine as a testament to Western Australia's mining heritage is not only a function of its success in the past but also of its ongoing modernisation and capacity for growth. This development goes hand in hand with the development witnessed by other major mines around the world in their effort to remain relevant and profitable through adopting new technologies and expanding their operations.
Diavik Diamond Mine, Canada
The Diavik Diamond Mine, on an island in Lac de Gras about 300 kilometres northeast of Yellowknife, is one of the principal examples of how solid modern mining enterprises can be in an adversary environment. Opened first in 2003, the mine, over a two-decade period, has been among the great contributors to Canada's diamond industry. With nearly 1,330 on-site employees today, Diavik has been a significant driver of employment and economic value in the region. To date, the mine has recovered over 144 million carats of diamonds- an astonishing figure representing enough diamonds to create more than 120 million engagement rings.
For the first time in four years since 2019, Diavik has opened its doors to a media tour with an objective toward transparency as it nears the end of its lifecycle. The decision to provide this inside look comes as Diavik prepares for the expected shutdown of operations by 2026, which will mark the culmination of its storied history. This milestone tour provided an opportunity for the public to gain insight into current operations, technological advancement, and responsible closure of the site.
Their success at the Diavik Diamond Mine has not only been due to its rich deposits but also to the innovative and adaptive approaches taken to mine in such a remote and hostile subarctic climate. The temperatures can often drop below freezing during winter, making equipment and workers extremely difficult. That this mine has been able to sustain these many years with heavy usage is a great testament to its engineering and logistical methods, which are very similar in nature to what can be seen in other successful mines around the globe. This large production and its contribution to the economy have left a mark on the Northwest Territories, indicating its vital contribution to Canada's position as one of the world's leading diamond producers. In this respect, Diavik is also a signal of how mining must be sustainable and responsibly done, with due consideration of ecological and social concerns along with economic benefits.
Betze-Post Mine, United States
The Betze-Post Mine is a large Goldstrike mining complex in Nevada and one of the largest and most productive gold mines in the world. The mine is almost 3.5 kilometres long and extends well over 500 meters down, which makes it one of the deepest and largest gold mines in the United States of America. Operated by Barrick Gold, Betze-Post Mine is one of the largest open pit mines that established Nevada as one of the world leaders in gold production.
In 2015, Betze-Post showed its enormous capacity with a production of 642,493 ounces (18,214.4 kg) of gold and 87,223 ounces (2,472.7 kg) of silver. Complementary to the open-pit mining, the underground operations in Meikle-Rodeo added a further 411,003 ounces (11,651.7 kg) of gold and 17,749 ounces (503.2 kg) of silver. Put together, these outputs accounted for 24% of Nevada's gold production in that year, given the fact that the state's total gold output for 2015 was 5,339,659 ounces - 151,376.8 kgs. By 2018, the Goldstrike complex anchored by Betze-Post produced 795,663 ounces of gold, ranking it the eighth largest gold mine in the world (learn more about mine security).
High-grade ore deposits and advanced extraction methods have underpinned Betze-Post's success. The mine's advanced processing facilities, including ore processing plants and heap leaching systems, ensure a high rate of gold recovery and optimum output. These capabilities have kept Betze-Post integral to Barrick Gold's portfolio and a cornerstone of Nevada's mining economy.
The Betze-Post represents the huge importance of mining due to its rich, complete history and continuing operation. It has been a case and point of strategic resource management and technological advancements that have kept it productive over the years. In addition, its operation has contributed to reinforcing local and state economies while reinforcing the region's status as a mining powerhouse. The ongoing process within the Goldstrike complex predicts that Betze-Post will continue to stand out as one of the leaders of gold production, a function of the resistance and economic importance of Nevada's mining industry.
Cerro Verde Mine, Peru
The Cerro Verde Mine is located in the southwestern part of Arequipa, Peru; it also happens to be among the largest copper ore-producing mines in the world. This giant open-pit mine is among those that contribute significantly to Peru's mining portfolio, accounting for about 17% of the total copper output and approximately 30% of molybdenum. During 2023, Cerro Verde was among the top five biggest copper producers in the world, with a production figure of 454 kt. The mine owners are Freeport-McMoRan, 53.56%; Sumitomo Metal Mining, 21%; Compañía de Minas Buenaventura, 19.58%; and others, 5.86% of minority ownership.
Recently, the Peruvian Ministry of Energy and Mines announced the approval of an ITS for the key expansion project at Cerro Verde, valued at over $600 million. The expansion reflects the mine's growing commitment to sustained growth and productivity. Currently, Cerro Verde can process more than 400,000 tonnes of ore per day, which is expected to increase with the expansion. The mine projects obtained an average of 420,000 tonnes of ore per day from 2026 to 2044, sustaining an annual average production of approximately 450 kt. This level of sustained production would enable Cerro Verde to stay relevant in the global copper supply chain.
Projections indicated that extraction would last until 2052, after which the reserves would be depleted. The future of the mine goes hand in hand with strategic planning and heavy investment for maximum long-term output. The expansion project not only secures the mine's future as a top-tier producer but also focuses on its importance to Peru's economy, reinforcing its status as a key contributor to employment and infrastructure development in the Arequipa region.
FAQ
What are open-pit mines, and why are they significant?
Open-pit mines are large excavations dug into the ground to extract valuable minerals and metals located close to the surface. Unlike underground mining, which requires tunnels and shafts, open-pit mining involves removing large quantities of soil and rock (overburden) to access ore deposits. These mines are significant due to their sheer scale and the volume of resources they produce, contributing immensely to the global supply of essential materials such as copper, gold, and diamonds. They showcase impressive engineering feats and have profound economic impacts on local and national economies. Examples like the Bingham Canyon Mine and the Escondida Mine demonstrate how open-pit mining can support sustained production for decades, providing jobs, infrastructure, and revenue.
What environmental and sustainability challenges do open-pit mines face?
Open-pit mines face several environmental challenges, including landscape disruption, habitat destruction, and pollution from mining operations. The removal of large amounts of overburden alters the natural landscape, affecting ecosystems and wildlife. Water usage is another significant concern, as mining often requires substantial amounts of water for ore processing, potentially straining local water supplies. Furthermore, emissions from machinery contribute to air pollution and greenhouse gas output. To address these challenges, many modern mines are integrating sustainable practices, such as using renewable energy sources, like solar and wind power, to reduce carbon footprints. Projects like the Cerro Verde Mine's expansion emphasise efficient water management and energy use, demonstrating the mining industry's shift towards more sustainable operations while maintaining productivity.
TAKEAWAY
The facts of the largest open pit mines tell a story of ambition, ingenuity, and adaptation. Each site embodies the spirit of human determination in harnessing Earth's resources for industrial and economic growth while still grappling with the profound responsibilities tied to such endeavours. This changeover, as seen at Chuquicamata and the Udachnaya operation, reflects the industry's ability to meet increasingly deeper extraction challenges. Meanwhile, the current and planned expansions, such as Fimiston and Cerro Verde, represent strategic decisions toward long-term viability.
Mining, in all its ramifications, continues to play a prime role in the development of the world, from supplying basic raw materials to powering economies and daily life. From these open-pit mines, we learn how growth in technology balances resource management with environmental sustainability. The probable emphasis that will be favoured later on is how these mining juggernauts can innovate further to maximise resource extraction with minimum ecological impairment. Their legacies remind one of the remarkable achievements and urgent responsibilities of one of the oldest industries in the world - a call to a future aligned with greater ecological harmony and community well-being.
Sources:
(1) https://projectblue.com/blue/news-analysis/909/peru-greenlights-cerro-verde-expansion
(2) https://www.ice.org.uk/what-is-civil-engineering/infrastructure-projects/kalgoorlie-super-pit
(3) https://www.mining-technology.com/projects/bingham/
(4) https://www.nsenergybusiness.com/projects/chuquicamata-copper-mine/
(5) https://www.mytruenorthnow.com/72879/featured/a-few-diamonds-more-the-closing-years-of-the-diavik-diamond-mine/
(6) https://www.mining-technology.com/projects/grasbergopenpit/
Author
Michal Wozniakowski-Zehenter, Marketing Manager
Michal Wozniakowski-Zehenter is an experienced marketing and project management professional. He spent most of his career on projects with a strong focus on digital marketing and event management. He is a very active voice representing offshore and mining industries through social media channels. Michal writes mainly about offshore oil and gas, renewable energy, mining and tunnelling. Compiling and sharing the knowledge within industries is one of his goals.
