Kittilä mine, also known as Suurikuusikko mine, is a

gold Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal ...

mine in

Kittilä Kittilä (, , ) is a municipalities of Finland, municipality of Finland and a popular holiday resort. It is located in northern Finland north of the Arctic Circle within the Lapland (Finland), Lapland Regions of Finland, region. The municipality ...

, in the Lapland County of

Finland Finland, officially the Republic of Finland, is a Nordic country in Northern Europe. It borders Sweden to the northwest, Norway to the north, and Russia to the east, with the Gulf of Bothnia to the west and the Gulf of Finland to the south, ...

. The mine is owned and operated by Agnico-Eagle Mines Limited and is located north-east of

. It is the largest gold mine in

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

. Exploration began in 1986, and production started in 2008. The mine is composed of two open pits, with the proceeds of the operation funding an underground mining operation, accessed by a ramp from surface and utilizing both transverse and longitudinal long-hole stoping methods. The mine utilizes on-site concentrating to produce Doré bars for shipment off-site for refinement, and produced of gold in 2009.

History

In 1986 gold was discovered near the town of Kittilä. The Geological Survey of Finland initiated exploration which resulted in a discovery of gold mineralization.

Diamond drilling Exploration diamond drilling is used in the mining industry to probe the contents of known ore deposits and potential sites. By withdrawing a small diameter core of rock from the orebody, geologists can analyze the core by Metallurgical assay, ch ...

continued up to 1991, when exploration ended. In 1998 the property was sold to Svenska Platina AB, a junior mining company which was a

subsidiary A subsidiary, subsidiary company, or daughter company is a company (law), company completely or partially owned or controlled by another company, called the parent company or holding company, which has legal and financial control over the subsidia ...

of Riddarhyttan Resources AB. Permitting for an

open pit mine Open-pit mining, also known as open-cast or open-cut mining and in larger contexts mega-mining, is a surface mining technique that extracts rock or minerals from the earth. Open-pit mines are used when deposits of commercially useful ore or r ...

began in 2002, with a mining licence and permit secured in 2003. Agnico Eagle purchased a stake in Riddarhyttan (at the time

feasibility studies A feasibility study is an assessment of the practicality of a project or system. A feasibility study aims to objectively and rationally uncover the strengths and weaknesses of an existing business or proposed venture, opportunities and threats pr ...

suggested the resource was between 2–3.7 million ounces of gold) in 2004, with the remainder of the company being purchased in 2005. Diamond drilling continued in 2005, with an additional 460 holes drilled over . In September 2008 an additional of drilling resulted in a gold reserve increase of two million ounces (5.7 million ounces total), over 18.2 million tonnes of ore, grading 5.12 grams per tonne. Excavation of the open pit began in September 2007 and ore production began in May 2008. Mining in the Suuri pit began at per day to be increased to by the end of 2009. In 2020, the Kittilä mine produced record amounts of of gold and 1.84 million metric tons of ore.

Mining operation

Open pit

left, Caterpillar 777 The ore zone at the Kittilä mine (mined by what are known as the Suuri and Roura pits) is approximately long, wide, deep. Drilling is done using both

Sandvik Sandvik AB is a Swedish multinational corporation, multinational engineering company specializing in products and services for mining, rock excavation, drilling rig, rock drilling, rock processing (crusher, crushing and mechanical screening, scre ...

and

Atlas Copco Atlas Copco (''Copco'' from Compagnie Pneumatique Commerciale) is a Swedish multinational industrial company that was founded in 1873. It manufactures industrial tools and equipment. The Atlas Copco Group is an industrial corpration with headq ...

drill rigs, with

ore Ore is natural rock or sediment that contains one or more valuable minerals, typically including metals, concentrated above background levels, and that is economically viable to mine and process. The grade of ore refers to the concentration ...

being loaded into

Caterpillar 777 dump truck The Caterpillar 777 is a 100-ton haul truck, typically used in open pit mining, manufactured by Caterpillar Inc Caterpillar Inc., also known as Cat, is an American construction, mining and other engineering equipment manufacturer. The compa ...

s (pictured) by

Caterpillar Caterpillars ( ) are the larval stage of members of the order Lepidoptera (the insect order comprising butterflies and moths). As with most common names, the application of the word is arbitrary, since the larvae of sawflies (suborder ...

385 hydraulic excavators. Mining in the pits is expected to last for up to five years. Proceeds from the pits are being used to finance the underground mining operation. The pit produces of material per month, removing eight tons of waste per ton of ore. Provided they are able to acquire larger trucks, Agnico will increase their monthly tonnage to .

Underground

Underground development began in October 2006. Access tunnels are wide, which will permit the use of haul trucks up to 60-tonne capacity. Underground mining will be done using long-hole stoping methods, either along

strike Strike may refer to: People *Strike (surname) * Hobart Huson, author of several drug related books Physical confrontation or removal *Strike (attack), attack with an inanimate object or a part of the human body intended to cause harm * Airstrike, ...

(longitudinal) in the case of narrow areas (less than ), and perpendicular (transverse) to the ore body in the case of wider zones. Levels are designed to be apart (from the floor to floor).

Processing

The

mill Mill may refer to: Science and technology * Factory * Mill (grinding) * Milling (machining) * Millwork * Paper mill * Steel mill, a factory for the manufacture of steel * Sugarcane mill * Textile mill * List of types of mill * Mill, the arithmetic ...

at the Kittila mine begins with a

crusher A crusher is a machine designed to reduce large rocks into smaller rocks, gravel, sand or rock dust. Crushers may be used to reduce the size, or change the form, of waste materials so they can be more easily disposed of or recycled, or to reduce ...

and semi-autogenous grinding mill (SAG Mill), where ore is sized to . The ore is then sent to flotation cells where the gold (located in

sulphide Sulfide (also sulphide in British English) is an inorganic anion of sulfur with the chemical formula S2− or a compound containing one or more S2− ions. Solutions of sulfide salts are corrosive. ''Sulfide'' also refers to large families of i ...

material) is separated from

gangue Gangue () is the commercially worthless material that surrounds, or is closely mixed with, a wanted mineral in an ore deposit. It is thus distinct from overburden, which is the waste rock or materials overlying an ore or mineral body that are di ...

material. The concentrated ore is sent to an

autoclave An autoclave is a machine used to carry out industrial and scientific processes requiring elevated temperature and pressure in relation to ambient pressure and/or temperature. Autoclaves are used before surgical procedures to perform steriliza ...

, and heated to 190, C at a pressure of . This heat and the addition of oxygen separates the gold from the sulphide material. The separated material is then leached out using

cyanide In chemistry, cyanide () is an inorganic chemical compound that contains a functional group. This group, known as the cyano group, consists of a carbon atom triple-bonded to a nitrogen atom. Ionic cyanides contain the cyanide anion . This a ...

. The carbon is removed from the leached material and the gold is

smelted Smelting is a process of applying heat and a chemical reducing agent to an ore to extract a desired base metal product. It is a form of extractive metallurgy that is used to obtain many metals such as iron, copper, silver, tin, lead and zinc. Sm ...

into Doré bars, which are sent off-site for further refining. Kittila realizes an average gold recovery of 92%, and has the capacity to produce up to four bars per week. The Kittila mill also includes a

bomb shelter A bomb shelter is a structure designed to provide protection against the effects of a bomb. Types of shelter Different kinds of bomb Shelter (building), shelters are configured to protect against different kinds of attack and strengths of host ...

, a legal requirement under a 1917 Finnish law which came into effect following Finnish independence from Russia. The shelter is open for viewing by visitors and contains emergency supplies such as oxygen tanks, food, drink and a set of golf clubs.

References

{{DEFAULTSORT:Kittila mine Underground mines in Finland Surface mines in Finland Gold mines in Finland