El Chino, located near Silver City, New Mexico, is an open-pit copper mine

Open-pit mining, or opencast mining, refers to a method of extracting rock or minerals from the earth by their removal from an open pit or borrow. The term is used to differentiate this form of mining from extractive methods that require tunneling into the earth. Open-pit mines are used when deposits of commercially useful minerals or rock are found near the surface; that is, where the overburden (surface material covering the valuable deposit) is relatively thin or the material of interest is structurally unsuitable for tunneling (as would be the case for sand, cinder, and gravel). The Chino open-pit copper mine located just out of Silver City, New Mexico. ... The Chino open-pit copper mine located just out of Silver City, New Mexico. ... Silver City is a town located in Grant County, New Mexico. ... The rocky side of a mountain creek near Orosí, Costa Rica. ... Minerals are natural compounds formed through geological processes. ... Pit may refer to: Look up Pit on Wiktionary, the free dictionary Any high walled depression in the ground, such as a quarry or (in Britain) a coal mine. ... A borrow pit is a term used in construction and civil engineering. ... The examples and perspective in this article or section may not represent a worldwide view. ... Minerals are natural compounds formed through geological processes. ... The rocky side of a mountain creek near Orosí, Costa Rica. ...

Where ofen find minerals that occur deep below the surface—where the overburden is thick or the mineral occurs as veins in hard rock— underground mining methods are used to extract the valued material. Open-pit mines are typically enlarged until the mineral resource is exhausted. Mineral resource classification involves organizing information on ores and other current or future economically important mineral deposits as a guidance for governmental and industrial planning. ...

Open-pit mines that produce building materials are commonly referred to as quarries. People in some English-speaking countries are not likely to make a distinction between an open-pit mine and other types of open-cast mines, such as quarries, borrows, placers, and strip mines. // Building material is any material which is used for a construction purpose. ... A small cinder quarry A dimension stone quarry A quarry is a type of open-pit mine from which rock or minerals are extracted. ... A borrow pit is a term used in construction and civil engineering. ... A sluice box used in placer mining Placer mining (pronounced plass-er) is a open-pit or open-cast form of mining by which certain valuable minerals are extracted from the earth without tunneling. ... Strip mining is the practice of mining a seam of mineral ore by first removing all of the soil and rock that lies on top of it. ...

When they are no longer productive for extraction of material, open-pit mines are sometimes converted to landfills for disposal of solid wastes. However, some form of water control is usually required to keep the mine pit from becoming a lake. A landfill compaction vehicle in operation A landfill, also known as a dump (US) or a tip (UK), is a site for the disposal of waste materials by burial and is the oldest form of waste treatment. ... This article or section does not cite its references or sources. ...

A coquina quarry

Quarry: Coquina, SC Image taken by me, released under GFDL Pollinator 05:40, 21 Mar 2004 (UTC) ( ) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Quarry: Coquina, SC Image taken by me, released under GFDL Pollinator 05:40, 21 Mar 2004 (UTC) ( ) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Categories: Stub ...

Extraction

Open Cut mines are dug on benches, which describe horizontal levels of the mine. These benches are usually on 3 metre or 6 metre levels, depending on the size of the machinery being used. Quarries rarely use benches, as the majority of quarries are dug using (relatively) small-scale machinery.

Most walls of the pit are generally dug on an angle less than vertical, to prevent and minimise damage and danger from rock falls. This depends on how weathered the rocks are, and the type of rock, and also how many structural weaknesses occur within the rocks, such as a fault, shears, joints or foliations. Old fault exposed by roadcut near Harrisburg, Pennsylvania. ... Study of geological shear is related to the study of structural geology, rock microstructure or rock texture and fault mechanics. ... Foliation is any penetrative planar fabric present in rocks. ...

The walls are stepped. The inclined section of the wall is known as the batter, and the flat part of the step is known as the bench or berm. The steps in the walls help prevent rock falls continuing down the entire face of the wall. In some instances additional ground support is required and rock bolts, cable bolts and shotcrete are used. De-watering bores may be used to relieve water pressure by drilling horizontally into the wall, which is often enough to cause failures in the wall by itself. A rock bolt is basically just a long anchor bolt, for stabilizing rock excavations, which may be tunnels or rock cuts. ...

A haul road is situated at the side of the pit, forming a ramp up which trucks can drive, carrying ore and waste rock. Trucks can refer to several things: The plural of: Truck, the motorized vehicle Truck, other uses of the singular As a name: Trucks was a rock band Trucks is a short story by Stephen King Trucks is a movie based on the Stephen King short story Trucks! is a television... Iron ore (Banded iron formation) Manganese ore Lead ore Gold ore An ore is a volume of rock containing components or minerals in a mode of occurrence which renders it valuable for mining. ...

Waste rock is piled up at surface near the edge of the open cut. This is known as the waste dump. The waste dump is also tiered and stepped, to minimise erosion. Severe soil erosion in a wheat field near Washington State University, USA. Erosion is the displacement of solids (soil, mud, rock and other particles) by the agents of wind, water or ice, by downward or down-slope movement in response to gravity or by living organisms (in the case of...

Ore which has been processed is known as tailings, and is generally a slurry. This is pumped to a tailings dam or settling pond, where the water evaporates. Tailings dams can often be toxic due to the presence of unextracted sulfide minerals, some forms of toxic minerals in the gangue, and often cyanide which is used to treat gold ore via the cyanide leach process. Tailings (also known as slickens[1]) are the waste left over[2] after removing the gangue from ore. ... Toxic redirects here, but this is also the name of a song by Britney Spears; see Toxic (song) Look up toxic and toxicity in Wiktionary, the free dictionary. ... The term sulfide (sulphide in British) refers to several types of chemical compounds containing sulfur in its lowest oxidation number of -2. ... Minerals are natural compounds formed through geological processes. ... A cyanide is any chemical compound that contains the cyano group -C≡N, with the carbon atom triple-bonded to the nitrogen atom. ... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ...

Open-pit mining at Garzweiler, Germany

Image File history File links Download high resolution version (12000x1464, 3569 KB) Description: Panorama of open-pit mining Garzweiler, Germany Source: own photography Date: 26. ... Image File history File links Download high resolution version (12000x1464, 3569 KB) Description: Panorama of open-pit mining Garzweiler, Germany Source: own photography Date: 26. ...

Rehabilitation

After mining finishes, the mine area must undergo rehabilitation. Waste dumps are contoured to flatten them out, to further stabilise them. If the ore contains sulfides it is usually covered with a layer of clay to prevent access of rain and oxygen from the air, which can oxidise the sulfides to produce sulfuric acid. This is then generally covered with soil, and vegetation is planted to help consolidate the material. Eventually this layer will erode, but it is generally hoped that the rate of leaching or acid will be slowed by the cover such that the environment can handle the load of acid and associated heavy metals. There are no long term studies on the success of these covers due to the relatively short time in which large scale open pit mining has existed. It may take hundreds to thousands of years for some waste dumps to become "acid neutral" and stop leaching to the environment. The dumps are usually fenced off to prevent livestock denuding them of vegetation. The open pit is then surrounded with a fence, to prevent access, and it generally eventually fills up with ground water. In arid areas it may not fill due to the deep groundwater levels. Land rehabilitation is the process of returning the land in a given area to some degree of its former self, after some process (business, industry, natural disaster etc. ... In chemistry, a sulfide (sulphide in British and Canadian English) is a combination of sulfur with an oxidation number of -2, with another chemical element or a radical thereof. ... The Gay Head cliffs in Marthas Vineyard are made almost entirely of natural clays. ... Rain falling For other uses see Rain (disambiguation). ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... Sulfuric acid (British English: sulphuric acid), H2SO4, is a strong mineral acid. ... Loess field in Germany Soil horizons are formed by combined biological, chemical and physical alterations. ... Sheep are commonly bred as livestock. ... A fence is a freestanding structure designed to restrict or prevent movement across a boundary. ... Groundwater is any water found below the land surface. ...

Typical open cut grades

Gold is generally extracted in open cut mines at 1 to 2 ppm (grams per ton) but in certain cases, 0.75ppm gold is economic. This was achieved by bulk heap leaching at Alkane Minerals Ltd. Peak Hill mine in western New South Wales, near Dubbo. General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ... Emblems: Floral - Waratah (Telopea speciosissima); Bird - Kookaburra (Dacelo gigas); Animal - Platypus (Ornithorhynchus anatinus); Fish - Blue Groper (Achoerodus viridis) Motto: Orta Recens Quam Pura Nites (Newly Risen, How Brightly You Shine) Slogan or Nickname: First State, Premier State Other Australian states and territories Capital Sydney Government Const. ... Dubbo is the largest population centre (population 38,000 as of 2004) and a Local Government Area in the central-west of New South Wales, Australia. ...

Nickel, generally as laterite, is extracted via open cut down to 0.2%. Copper is extracted at grades as low as 0.15% to 0.2%, generally in massive open cut mines in Chile, where the size of the resources and favorable metallurgy allows economies of scale. General Name, Symbol, Number nickel, Ni, 28 Chemical series transition metals Group, Period, Block 10, 4, d Appearance lustrous, metallic Atomic mass 58. ... General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance metallic pinkish red Atomic mass 63. ... Metallurgy is a domain of materials science and of materials engineering that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their mixtures, which are called alloys. ...

Materials typically extracted from open-pit mines include:

• Clay
• Coal
• Coquina
• Gravel and stone (stone refers to bedrock, while gravel is unconsolidated material, as found in glacial or fluvial deposits)
• Granite
• Gritstone
• Gypsum
• Limestone
• Marble
• Metal ores, such as copper, iron, gold, and molybdenum
• Oil shale
• Sand
• Sandstone
• Slate

The Gay Head cliffs in Marthas Vineyard are made almost entirely of natural clays. ... Coal Coal (IPA: ) is a fossil fuel extracted from the ground by underground mining or open-pit mining (surface mining). ... Categories: Stub ... Gravel being unloaded from a barge Gravel is rock that is of a certain grain size range. ... The rocky side of a mountain creek near Orosí, Costa Rica. ... A glacier is a large, long-lasting river of ice that is formed on land and moves in response to gravity. ... The word fluvial is used in geography and earth science to refer to all topics related to flowing water. ... Quarrying granite for the Mormon Temple, Utah Territory. ... Gritstone is a sedimentary rock composed of coarse sand grains and is a coarser version of sandstone. ... Gypsum is a very soft mineral composed of calcium sulfate dihydrate, with the chemical formula CaSO4·2H2O. // [edit] Chemical structure Heating gypsum to between 100°C and 150°C (302°F) partially dehydrates the mineral by driving off exactly 75% of the water contained in its chemical structure. ... Limey shale overlaid by limestone. ... Venus de Milo, front. ... Hot metal work from a blacksmith In chemistry, a metal (Greek: Metallon) is an element that readily forms positive ions (cations) and has metallic bonds. ... An ore is a mineral deposit containing a metal or other valuable resource in economically viable concentrations. ... General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance metallic pinkish red Atomic mass 63. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Atomic mass 55. ... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Atomic mass 196. ... General Name, Symbol, Number molybdenum, Mo, 42 Chemical series transition metals Group, Period, Block 6, 5, d Appearance gray metallic Atomic mass 95. ... Oil shale is a general term applied to a group of rocks rich enough in organic material (called kerogen) to yield petroleum upon distillation. ... Patterns in the sand Sand is an example of a class of materials called granular matter. ... Red sandstone interior of Lower Antelope Canyon, Arizona, worn smooth due to erosion by flash flooding over millions of years Sandstone is a sedimentary rock composed mainly of sand-size mineral or rock grains. ... Slate Slate is a fine-grained, homogeneous, metamorphic rock derived from an original sedimentary rock composed of clay or volcanic ash through low grade regional metamorphism. ...

Open-pit mines

The Lavender Pit, Bisbee, Arizona

This list includes only those large open-pit mines for which an article exists in Wikipedia. Image File history File linksMetadata Download high-resolution version (1200x1600, 685 KB) The Lavender Pit, an open pit copper mine, Bisbee, Arizona. ... Image File history File linksMetadata Download high-resolution version (1200x1600, 685 KB) The Lavender Pit, an open pit copper mine, Bisbee, Arizona. ... Bisbee is a city located in Cochise County, Arizona, USA, 82 miles (132 km) southeast of Tucson. ...

• Adams Mine – controversial abandoned mine in Kirkland Lake, Ontario.
• Berkeley Pit - former copper mine in Butte, Montana, United States; now a toxic lake.
• Chuquicamata – Chilean copper mine; largest open-pit mine in the world
• Colomac Mine – gold mine in Northwest Territories, Canada.
• Cerrejón – coal mine in Guajira Department, Colombia.
• Diavik Diamond Mine – diamond mine in Northwest Territories, Canada.
• Ekati Diamond Mine – diamond mine in Northwest Territories, Canada.
• El Chino Mine – copper mine in Grant County, New Mexico, United States

• Kennecott Copper Mine – largest excavation in the world; copper mine in Salt Lake County, Utah, United States;
• Lavender Pit – copper mine in Cochise County, Arizona, United States.
• Mirny Mine – diamond mine in Mirny, Eastern Siberia
• Pascua Lama – gold and silver mine in Atacama, Chile (in project)
• Penrhyn Quarry – slate quarry in Wales.
• Pine Point Mine – lead and zinc mine in Northwest Territories, Canada.
• Super Pit – gold mine near Kalgoorlie, Western Australia.
• The Big Hole, a diamond mine in Kimberley, South Africa that reaches a depth of more than 1,000 m (3,300 ft).
• Udachnaya pipe – diamond mine in Yakutia, Russia.

Adams Mine is an abandoned open pit mine in Boston Township near Kirkland Lake, Ontario, which was the cornerstone of a controversial waste management plan in the 1990s. ... Kirkland Lake is a town located in Timiskaming District in northeastern Ontario, Canada. ... The Berkeley Pit is a gigantic former open pit copper mine located in Butte, Montana, and is the largest Superfund site. ... Butte, Montana Butte is a city that is located in Silver Bow County, Montana and is the county seat. ... This article or section does not cite its references or sources. ... One of the larger pits in the base of the open cast mine Chuquicamata copper mine in 1984 Chuquicamata, or, Chuqui, as it is commonly called, is the largest open pit copper mine in the world. ... The Colomac Mine was an open pit gold mine in the Northwest Territories that operated between 1990-1992, and 1994-1997. ... Motto: None Official languages Dene Suline, Cree, Dogrib, English, French, Gwichʼin, Inuktitut, Slavey Flower Mountain avens Capital Yellowknife Largest city Yellowknife Commissioner Tony Whitford Premier Joe Handley (Consensus government - no party affiliations) Parliamentary representation  - House seat  - Senate seats 1 1 Area Total  - Land  - Water    (% of total)  Ranked 3rd 1... Cerrejón is a coal mine located in the Guajira department in the north of Colombia. ... La Guajira is a department of Colombia. ... The Diavik Diamond Mine is a very large diamond mine located in the Northwest Territories, about 300 km north of Yellowknife. ... Diamond Mine is also another name for the computer game Bejeweled. ... Motto: None Official languages Dene Suline, Cree, Dogrib, English, French, Gwichʼin, Inuktitut, Slavey Flower Mountain avens Capital Yellowknife Largest city Yellowknife Commissioner Tony Whitford Premier Joe Handley (Consensus government - no party affiliations) Parliamentary representation  - House seat  - Senate seats 1 1 Area Total  - Land  - Water    (% of total)  Ranked 3rd 1... The Ekati Diamond Mine is Canadas first operational diamond mining operation. ... Motto: None Official languages Dene Suline, Cree, Dogrib, English, French, Gwichʼin, Inuktitut, Slavey Flower Mountain avens Capital Yellowknife Largest city Yellowknife Commissioner Tony Whitford Premier Joe Handley (Consensus government - no party affiliations) Parliamentary representation  - House seat  - Senate seats 1 1 Area Total  - Land  - Water    (% of total)  Ranked 3rd 1... The El Chino mine located near Silver City, New Mexico The El Chino (or just Chino) Mine is an open-pit copper mine located near Silver City, New Mexico. ... Grant County is a county located in the state of New Mexico. ... Capital Santa Fe Largest city Albuquerque Area  Ranked 5th  - Total 121,665 sq mi (315,194 km²)  - Width 342 miles (550 km)  - Length 370 miles (595 km)  - % water 0. ... The Bingham Canyon mine is the largest man-made excavation on earth. ... Salt Lake County is a county located in the state of Utah. ... Official language(s) English Capital Salt Lake City Largest city Salt Lake City Area  Ranked 13th  - Total 84,876 sq mi (219,887 km²)  - Width 270 miles (435 km)  - Length 350 miles (565 km)  - % water 3. ... The Lavender Pit is an open pit copper mine located in Cochise County, Bisbee, Arizona. ... Location in the state of Arizona Formed 1881 Seat Bisbee Area  - Total  - Water 16,107 km² (6,219 mi²) 128 km² (49 mi²) 0. ... Official language(s) English Capital Phoenix Largest city Phoenix Area  Ranked 6th  - Total 113,998 sq mi (295,254 km²)  - Width 310 miles (500 km)  - Length 400 miles (645 km)  - % water 0. ... Mir Mine (Russian: ; English: kimberlite diamond pipe Peace) is an abandoned open pit diamond mine located in Mirny, Eastern Siberia. ... Mirny can refer to: Russian language for peaceful the city Mirny, Sakha in Russia the city Mirny, Arkhangelsk in Russia the Russian Mirny Station in the Antarctica See also: List of places named after peace This is a disambiguation page — a navigational aid which lists other pages that might... Siberian Federal District (dark red) and the broadest definition of Siberia (red) Udachnaya pipe Siberia (Russian: , Sibir; Tatar: ) is a vast region of Russia constituting almost all of Northern Asia. ... Pascua-Lama is a project aiming at exploitation of a very rich field of gold and silver in the high mountains south of Atacama, at the boarder between Chile and Argentina, in an area approximately 150 kilometers southeast of Vallenar and 300 kilometers northwest of San Juan. ... Atacama The Atacama Desert of Chile is a virtually rainless plateau made up of salt basins (salares), sand, and lava flows, extending from the Andes mountains to the Pacific Ocean. ... The Penrhyn Slate Quarry is a slate quarry located near Bethesda in north Wales. ... The slate industry is the industry related to the extraction and processing of slate. ... Motto: (Welsh for Wales forever) Anthem: Hen Wlad Fy Nhadau Capital Cardiff Largest city Cardiff Official language(s) English, Welsh Government Constitutional monarchy  - Queen Queen Elizabeth II  - Prime Minister Tony Blair MP  - First Minister Rhodri Morgan AM Unification    - by Gruffudd ap Llywelyn 1056  Area    - Total 20,779 km² (3rd in... The past producing Pine Point Mine is located west of Fort Resolution and east of Hay River, Northwest Territories, on the south shore of Great Slave Lake, Northwest Territories. ... Motto: None Official languages Dene Suline, Cree, Dogrib, English, French, Gwichʼin, Inuktitut, Slavey Flower Mountain avens Capital Yellowknife Largest city Yellowknife Commissioner Tony Whitford Premier Joe Handley (Consensus government - no party affiliations) Parliamentary representation  - House seat  - Senate seats 1 1 Area Total  - Land  - Water    (% of total)  Ranked 3rd 1... Large gold mine near Kalgoorlie-Boulder, Western Australia External Links http://www1. ... Kalgoorlie is a Western Australian city located about 600 km east of Perth. ... The Big Hole is a huge open-pit mine in Kimberley, South Africa. ... Kimberley is a town in South Africa, and the capital of the Northern Cape. ... View of the Udachnaya open pit. ... The Sakha (Yakutia) Republic (Russian: ; Yakut: Саха Республиката) is a federal subject of Russia (a republic). ...

See also

• List of minerals
• List of stone
• Definition of "ore"
• Ore genesis
• Mineral resource classification