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87-605: Dempo Mining Corporation Limited is a prominent mining company from the western Indian state of Goa . The mineral business was founded by Vasantrao S. Dempo in 1941, along with his younger brother Vaikuntrao Dempo. Vasantrao S. Dempo was the founding chairman of the company, succeeded by his son Vasudeva V. Dempo. Currently, Shrinivas V. Dempo, son of Vasudeva, is the chairman of Dempo Group. In June 2011, Vedanta Limited acquired Dempo Group's mining assets for ₹ 17.5 billion (US$ 210 million). Dempo has divested its mining assets and entered different businesses. The following are

174-512: A crisis because this is used for drinking and farmland. There are many different ways that illegal mining destructs ecosystems. Illegal gold mining operations used heavy metals such as mercury and cyanide to extract gold from waste material. The mercury and cyanide leach into the natural environment causing pollution.  Illegal miners often dump excess mercury into the nearby waterways for disposal.  Water pollution affects surrounding communities, aquatic ecosystems and land ecosystems due to

261-636: A hopper and a shaking screen or trommel which frees the desired minerals from the waste gravel. The minerals are then concentrated using sluices or jigs. Large drills are used to sink shafts, excavate stopes, and obtain samples for analysis. Trams are used to transport miners, minerals and waste. Lifts carry miners into and out of mines, and move rock and ore out, and machinery in and out, of underground mines. Huge trucks, shovels and cranes are employed in surface mining to move large quantities of overburden and ore. Processing plants use large crushers, mills, reactors, roasters and other equipment to consolidate

348-883: A mass of actual rock. Both types of ore deposit, placer or lode, are mined by both surface and underground methods. Some mining, including much of the rare earth elements and uranium mining , is done by less-common methods, such as in-situ leaching : this technique involves digging neither at the surface nor underground. The extraction of target minerals by this technique requires that they be soluble, e.g., potash , potassium chloride , sodium chloride , sodium sulfate , which dissolve in water. Some minerals, such as copper minerals and uranium oxide , require acid or carbonate solutions to dissolve. Explosives in Mining Explosives have been used in surface mining and sub-surface mining to blast out rock and ore intended for processing. The most common explosive used in mining

435-426: A mining operation. Once the analysis determines a given ore body is worth recovering, development begins to create access to the ore body. The mine buildings and processing plants are built, and any necessary equipment is obtained. The operation of the mine to recover the ore begins and continues as long as the company operating the mine finds it economical to do so. Once all the ore that the mine can produce profitably

522-503: A more sustainable future, the demand for metals is set to skyrocket. Between 2022 and 2050, an estimated 7 billion metric tons of metals will need to be extracted. Steel will account for the largest portion of this total at 5 billion tons, followed by aluminum at 950 million tons, copper at 650 million tons, graphite at 170 million tons, nickel at 100 million tons, and other metals. Notably, the energy expenditure required to extract these metals will soon surpass that of coal mining, highlighting

609-763: A negative environmental impact, both during the mining activity and after the mine has closed. Hence, most of the world's nations have passed regulations to decrease the impact; however, the outsized role of mining in generating business for often rural, remote or economically depressed communities means that governments often fail to fully enforce such regulations. Work safety has long been a concern as well, and where enforced, modern practices have significantly improved safety in mines. Unregulated, poorly regulated or illegal mining , especially in developing economies , frequently contributes to local human rights violations and environmental conflicts . Mining can also perpetuate political instability through resource conflicts . Since

696-406: A proposed mine, extraction of the desired materials, and final reclamation or restoration of the land after the mine is closed. Mining materials are often obtained from ore bodies, lodes , veins , seams , reefs , or placer deposits . The exploitation of these deposits for raw materials is dependent on investment, labor, energy, refining, and transportation cost. Mining operations can create

783-408: A strong inducement to extract these metals or to lease the deposits and collect royalties from mine operators. English, German , and Dutch capital combined to finance extraction and refining . Hundreds of German technicians and skilled workers were brought over; in 1642 a colony of 4,000 foreigners was mining and smelting copper at Keswick in the northwestern mountains. Use of water power in

870-428: A subsistence activity, as is the case with artisanal mining , or it can belong to large-scale organized crime , spearheaded by illegal mining syndicates. On an international level, approximately 80 percent of small-scale mining operations can be categorized as illegal. Despite strategic developments towards " responsible mining ," even big companies can be involved in illegal mineral digging and extraction, if only on

957-512: A task force that was created to remove all illegal mining operations due to the environmental problems it has caused. The environmental and water quality deterioration caused the President of Ghana to make a press release to explain the urgency and need for public support to aid in fixing the problem. Illegal mining operations in Ghana have contributed to the reduction of poverty. Illegal mining

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1044-654: A third of Hindustan Unilever’s beverage business. It also works with companies like Danone and Lipton . Sensing the tourism potential of Goa, the Dempo Travel Agency was established in 1960 as a travel division of the flagship V. S. Dempo & Company Pvt. Ltd., and has been one of the mainstays of Goan tourism industry. In 2000-01, a new company, Dempo Travels Pvt. Ltd. was formed to handle this business independently. The two main divisions under this company are Navhind Papers, and Publications and Energy division. Apart from writers of national repute, it features

1131-651: Is ammonium nitrate . Between 1870 and 1920, in Queensland Australia, an increase in mining accidents lead to more safety measures surrounding the use of explosives for mining. In the United States of America, between 1990 and 1999, about 22.3 billion kilograms of explosives were used in mining quarrying and other industries; Moreover " coal mining used 66.4%, nonmetal mining and quarrying 13.5%, metal mining 10.4%, construction 7.1%, and all other users 2.6%". Artisanal and small-scale mining (ASM)

1218-510: Is 240,000 MT per annum. Based on Tata korf technology, this mini blast furnace -based technology has a capacity of 160,000 TPA. Devashri Real Estate Developers was launched by the Dempo family with projects in Panaji , Taleigao , Porvorim , Vasco , Caranzalem and Candolim . Mining Modern mining processes involve prospecting for ore bodies, analysis of the profit potential of

1305-811: Is a blanket term for a type of subsistence mining involving a miner who may or may not be officially employed by a mining company but works independently, mining minerals using their own resources, usually by hand. While there is no completely coherent definition for ASM, artisanal mining generally includes miners who are not officially employed by a mining company and use their own resources to mine. As such, they are part of an informal economy . ASM also includes, in small-scale mining, enterprises or individuals that employ workers for mining, but who generally still use similar manually-intensive methods as artisanal miners (such as working with hand tools). In addition, ASM can be characterized as distinct from large-scale mining (LSM) by less efficient extraction of pure minerals from

1392-404: Is a well-documented phenomenon in sub-Saharan Africa . While legalization opportunities for artisanal and small scale mining are often available, inefficient government bureaucracy structures can make noncompliance more appealing for workers. In addition, in an effort to attract foreign investment, many governments in sub-Saharan Africa have loosened national mining investment codes. An expansion of

1479-476: Is done by removing surface vegetation, dirt, and bedrock to reach buried ore deposits. Techniques of surface mining include: open-pit mining , which is the recovery of materials from an open pit in the ground; quarrying , identical to open-pit mining except that it refers to sand, stone and clay; strip mining , which consists of stripping surface layers off to reveal ore underneath; and mountaintop removal , commonly associated with coal mining, which involves taking

1566-518: Is generally facilitated by middlemen who falsify documentation to ease the transition into the legitimate international marketplace. Mining scams in India (colloquially Indian mining scam) refers to a series of alleged widespread scams in various ore-rich states of India , which has generated controversy. Such issues span encroachment of forest areas, underpayment of government royalties, and conflict with tribals regarding land rights. The spill-over of

1653-470: Is impacted by illegal mining activity because of land degradation and availability. There is less available land for farming causing competition and higher costs for farmers. The illegal miners trespass through farmland to construct roads through farms destroying the cocoa trees in the process. They also mine on the farmland which is where many farmers die because of falling into the pits. Illegal mining operations cause flooding with polluted water that affects

1740-613: Is mining upward, creating a sloping underground room, long wall mining , which is grinding a long ore surface underground, and room and pillar mining, which is removing ore from rooms while leaving pillars in place to support the roof of the room. Room and pillar mining often leads to retreat mining , in which supporting pillars are removed as miners retreat, allowing the room to cave in, thereby loosening more ore. Additional sub-surface mining methods include hard rock mining , bore hole mining, drift and fill mining, long hole slope mining, sub level caving, and block caving . Heavy machinery

1827-484: Is much more common, and produces, for example, 85% of minerals (excluding petroleum and natural gas) in the United States, including 98% of metallic ores. Targets are divided into two general categories of materials: placer deposits , consisting of valuable minerals contained within river gravels, beach sands, and other unconsolidated materials ; and lode deposits , where valuable minerals are found in veins, in layers, or in mineral grains generally distributed throughout

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1914-413: Is not of immediate interest to the miner. The total movement of ore and waste constitutes the mining process. Often more waste than ore is mined during the life of a mine, depending on the nature and location of the ore body. Waste removal and placement is a major cost to the mining operator, so a detailed characterization of the waste material forms an essential part of the geological exploration program for

2001-584: Is recovered, reclamation can begin, to make the land used by the mine suitable for future use. Technical and economic challenges notwithstanding, successful mine development must also address human factors. Working conditions are paramount to success, especially with regard to exposures to dusts, radiation, noise, explosives hazards, and vibration, as well as illumination standards. Mining today increasingly must address environmental and community impacts, including psychological and sociological dimensions. Thus, mining educator Frank T. M. White (1909–1971), broadened

2088-656: Is the largest producer of diamonds in Africa, with an estimated 12 million carats in 2019. Other types of mining reserves in Africa include cobalt , bauxite , iron ore , coal, and copper . Gold and coal mining started in Australia and New Zealand in the 19th century. Nickel has become important in the economy of New Caledonia . In Fiji , in 1934, the Emperor Gold Mining Company Ltd. established operations at Vatukoula , followed in 1935 by

2175-423: Is to conduct a feasibility study to evaluate the financial viability, the technical and financial risks, and the robustness of the project. This is when the mining company makes the decision whether to develop the mine or to walk away from the project. This includes mine planning to evaluate the economically recoverable portion of the deposit, the metallurgy and ore recoverability, marketability and payability of

2262-514: Is unregulated and illegal, are substantial, contributing to 37 percent of the atmospheric mercury emitted annually. While drug trafficking has historically been a prominent criminal enterprise , lower risks associated with illegal mining have propelled a shift toward lucrative illegal gold mining operations. In order to transfer illegal gold into the marketplace, criminal actors sometimes attempt to mask its illicit origins by melting together processed legal and illegal gold. This gold laundering task

2349-419: Is used in mining to explore and develop sites, to remove and stockpile overburden, to break and remove rocks of various hardness and toughness, to process the ore, and to carry out reclamation projects after the mine is closed. Bulldozers, drills, explosives and trucks are all necessary for excavating the land. In the case of placer mining , unconsolidated gravel, or alluvium , is fed into machinery consisting of

2436-521: The Greek author Diodorus Siculus , who mentions fire-setting as one method used to break down the hard rock holding the gold . One of the complexes is shown in one of the earliest known mining maps. The miners crushed the ore and ground it to a fine powder before washing the powder for the gold dust known as the dry and wet attachment processes. Mining in Europe has a very long history. Examples include

2523-517: The argentiferous galena in the mines of Cartagena ( Cartago Nova ), Linares ( Castulo ), Plasenzuela and Azuaga , among many others. Spain was one of the most important mining regions, but all regions of the Roman Empire were exploited. In Great Britain the natives had mined minerals for millennia , but after the Roman conquest , the scale of the operations increased dramatically, as

2610-836: The greenstone of the Langdale axe industry based in the English Lake District . The oldest-known mine on archaeological record is the Ngwenya Mine in Eswatini (Swaziland) , which radiocarbon dating shows to be about 43,000 years old. At this site Paleolithic humans mined hematite to make the red pigment ochre . Mines of a similar age in Hungary are believed to be sites where Neanderthals may have mined flint for weapons and tools. Ancient Egyptians mined malachite at Maadi . At first, Egyptians used

2697-509: The 21st century begins, a globalized mining industry of large multinational corporations has arisen. Peak minerals and environmental impacts have also become a concern. Different elements, particularly rare-earth minerals , have begun to increase in demand as a result of new technologies. In 2023, 8.5 billion metric tons of coal were extracted from the Earth's crust. However, as the global economy transitions away from fossil fuels and toward

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2784-680: The 7th century to the 14th century. Gold was often traded to Mediterranean economies that demanded gold and could supply salt , even though much of Africa was abundant with salt due to the mines and resources in the Sahara desert . The trading of gold for salt was mostly used to promote trade between the different economies. Since the Great Trek in the 19th century, after, gold and diamond mining in Southern Africa has had major political and economic impacts. The Democratic Republic of Congo

2871-675: The French crown to operate mines in 1733, becoming "the first practical miner on Lake Superior"; seven years later, mining was halted by an outbreak between Sioux and Chippewa tribes. Mining in the United States became widespread in the 19th century, and the United States Congress passed the General Mining Act of 1872 to encourage mining of federal lands. As with the California Gold Rush in

2958-643: The Loloma Gold Mines, N.L., and then by Fiji Mines Development Ltd. (aka Dolphin Mines Ltd.). These developments ushered in a “mining boom”, with gold production rising more than a hundred-fold, from 931.4 oz in 1934 to 107,788.5 oz in 1939, an order of magnitude then comparable to the combined output of New Zealand and Australia's eastern states. During prehistoric times, early Americans mined large amounts of copper along Lake Superior 's Keweenaw Peninsula and in nearby Isle Royale ; metallic copper

3045-481: The Romans needed Britannia 's resources, especially gold , silver , tin , and lead . Roman techniques were not limited to surface mining. They followed the ore veins underground once opencast mining was no longer feasible. At Dolaucothi they stoped out the veins and drove adits through bare rock to drain the stopes. The same adits were also used to ventilate the workings, especially important when fire-setting

3132-598: The Spanish to pulverize ore after being mined. This device was powered by animals and used the same principles used for grain threshing . Much of the knowledge of medieval mining techniques comes from books such as Biringuccio 's De la pirotechnia and probably most importantly from Georg Agricola 's De re metallica (1556). These books detail many different mining methods used in German and Saxon mines. A prime issue in medieval mines, which Agricola explains in detail,

3219-756: The Umm el-Sawwan site; gypsum was used to make funerary items for private tombs. Other minerals mined in Egypt from the Old Kingdom (2649-2134 BC) until the Roman Period (30 BC-AD 395) including granite , sandstone , limestone , basalt , travertine , gneiss , galena , and amethyst . Mining in Egypt occurred in the earliest dynasties. The gold mines of Nubia were among the largest and most extensive of any in Ancient Egypt. These mines are described by

3306-624: The beginning of civilization, people have used stone , clay and, later, metals found close to the Earth's surface. These were used to make early tools and weapons; for example, high quality flint found in northern France , southern England and Poland was used to create flint tools . Flint mines have been found in chalk areas where seams of the stone were followed underground by shafts and galleries. The mines at Grimes Graves and Krzemionki are especially famous, and like most other flint mines, are Neolithic in origin (c. 4000–3000 BC). Other hard rocks mined or collected for axes included

3393-528: The bright green malachite stones for ornamentations and pottery . Later, between 2613 and 2494 BC, large building projects required expeditions abroad to the area of Wadi Maghareh in order to secure minerals and other resources not available in Egypt itself. Quarries for turquoise and copper were also found at Wadi Hammamat , Tura , Aswan and various other Nubian sites on the Sinai Peninsula and at Timna . Quarries for gypsum were found at

3480-517: The cartels to earn a larger profit than the drug trade with lower risk. Illegal mining operations controlled by organized crime groups are hazardous to the miners but many are drawn to the work due to the effect it has on the surrounding environment.  Child labour is very common in the mines because children are trafficked and forced into work. Adults are also exploited, trafficked and forced into unsafe labour conditions. Illegal mining operations affect surrounding agriculture. Cocoa farming in Ghana

3567-556: The clearcutting of forests in regions where illegal mining occurs. Deforestation contributes to soil erosion since the roots of trees provide the soil with stability.  There have been many efforts to protect and rehabilitate forest ecosystems in recent years to prevent and limit the effects of deforestation. Illegal mining causes soil erosion and degradation which leads to barren lands where nothing can survive. Soil erosion reduces soil fertility which affects agricultural lands. Soil degradation occurs (1) when removing topsoil affects

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3654-479: The companies which are fully or partially owned by the House of Dempo: This Dempo Group company, established in 1988 as a joint venture with Glaxo , manufactures cereal -based food products including baby foods. The range encompasses instant porridge , breakfast cereals and health drinks. The Vanity Case Group, led by Sameer Kothari, acquired a majority stake in 2013. The company is responsible for manufacturing about

3741-417: The cutter-head is progressively launched further into the coal seam. High wall mining can produce thousands of tons of coal in contour-strip operations with narrow benches, previously mined areas, trench mine applications and steep-dip seams. Sub-surface mining consists of digging tunnels or shafts into the earth to reach buried ore deposits. Ore, for processing, and waste rock, for disposal, are brought to

3828-525: The effects of legal mining into issues such as Naxalism and the distortion of the Indian political system by mixed politics and mining interests, has gained international attention. The Nigerian government does not have the funds needed to enforce the law that prohibits illegal mining. They do not have the capacity and authority for the full enforcement of the law.  Government funds are affected by illegal mining operations because they cannot profit from

3915-572: The environment because there are no efforts to treat the soil to get rid of toxic chemicals. Soil erosion leads to natural hazards such as landslides due to loose soil and flooding. Latin America is the centre of the global drug trade since that’s where most drugs are produced. Organized crime groups such as drug cartels realized the profitability and began to illegally mine precious metals.  These groups were able to get control of large amounts of land away from government surveillance. This allowed

4002-605: The environment they are mining which causes the environment to be complete destroyed by the illegal activity. Certified mining causes less of a threat and destruction to the environment than illegal mining because of the guidelines they are required to follow to be perverse the environment while extracting resources. Illegal miners create large mining pits that are not back filled when they are finished, many people and animals die from these pits. Due to run off from illegal mining activity contaminates surface water and underground water with mud, mercury and cyanide . This pollution creates

4089-417: The extraction of metals. Nigeria is rich in precious metals which causes foreign illegal mining operations to come to Nigeria. This causes violence and conflict between the local and foreign illegal miners in some parts of Nigeria. The vastness of Nigeria causes remote places where illegal mining operations can occur without the government having any knowledge of it. In Ghana, the government has put together

4176-469: The fertility of the soil and decreases the chance of restoring vegetation. (2) When toxic chemicals pollute soil to an extent where plants cannot grow. The toxins deplete the soil's nutrients and inhibit vegetation.  (3) When large amounts of mining waste such as rock, sediment and soil that lacks nutrients are dumped onto the land it stops the growth of plants. This waste engulfs topsoil taking away fertility. Poorly contained mining tails are hazardous to

4263-419: The financing side. Large-scale mining operations are owned by large companies nationally and use advanced technology to extract metals; these operations use open-pit mining.  Artisanal small-scale mining operations are labour-intensive mining because miners do not use machinery to extract the metals.  Informal mining occurs when artisanal small-scale mining operations proceed in mining activity without

4350-698: The focus to the “total environment of mining”, including reference to community development around mining, and how mining is portrayed to an urban society, which depends on the industry, although seemingly unaware of this dependency. He stated, “[I]n the past, mining engineers have not been called upon to study the psychological, sociological and personal problems of their own industry – aspects that nowadays are assuming tremendous importance. The mining engineer must rapidly expand his knowledge and his influence into these newer fields.” Mining techniques can be divided into two common excavation types: surface mining and sub-surface (underground) mining . Today, surface mining

4437-487: The form of water mills was extensive. The water mills were employed in crushing ore, raising ore from shafts, and ventilating galleries by powering giant bellows . Black powder was first used in mining in Selmecbánya , Kingdom of Hungary (now Banská Štiavnica , Slovakia) in 1627. Black powder allowed blasting of rock and earth to loosen and reveal ore veins. Blasting was much faster than fire-setting and allowed

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4524-525: The growing business. This company has already built a number of barges. Manufacturer and marketer of calcined petroleum coke , this Dempo Group company is listed on the Bombay Stock Exchange. Goa Carbon is the second largest manufacturer of calcined petroleum coke in the country. Goa Carbon was established in 1976. It has manufacturing facilities in Goa, Paradeep , and Bilaspur . Total capacity

4611-400: The growing importance of sustainable metal extraction practices. The process of mining from discovery of an ore body through extraction of minerals and finally to returning the land to its natural state consists of several distinct steps. The first is discovery of the ore body, which is carried out through prospecting or exploration to find and then define the extent, location and value of

4698-402: The hydraulic cycle. The polluted water is used for irrigation of farmland and community use, this further spreads pollution which leads to illness and death. Deforestation occurs during illegal mining operations so mining operations have room to function. As forests are clear-cut and the ground is mined, ecosystems collapse due to habitat loss.  Carbon emissions increase drastically due to

4785-471: The increase in population, mosquitoes have a greater risk of carrying malaria. When illegal mining operations abandon their pits, there is no way for local authorities to track and prevent the open pits to decrease the spread. Illegal miners also do not take proper precautions to protect themselves when mining and it increases the risk of transmission. Spurred by widespread poverty and a lack of alternative income-earning opportunities, illegal artisanal mining

4872-462: The large-scale mining projects fuelled by foreign investment has displaced rural mining communities, many of which revert to illegal mining on concessions given to the formal mining sector. As a response measure, Ghana for instance launched Operation Vanguard in 2017 to restrain illegal artisanal mining in Ghana. Latin America is home to the Amazon rainforest which has many ecosystems living within

4959-518: The laws and environment while mining.  Corruption in privately owned large-scale mining and artisanal small-scale mining operations occurs because the operations delegate their power to local authorities.  The lack of coordination allows loopholes for corruption. The laws and procedures surrounding mining lessen the impact on the environment and are violated by large and artisanal small-scaling contributing to environmental damage. Illegal miners generally lack knowledge and simply do not care about

5046-512: The maturation of the cocoa pods.  Flooding depletes soil fertility, increases erosion and affects the farmer's ability to grow cocoas trees. These factors contribute to farmers’ fear of losing their livelihood due to the losses that are caused by illegal mining. Abandoned open-pit mines cause an increase in the mosquito population which can increase the spread of malaria . These pits fill up with stagnant or slow-moving bodies of water where mosquitoes can breed and their larvae can grow. Due to

5133-535: The metals due to the difficulties of transporting them, but the copper was eventually traded throughout the continent along major river routes. In the early colonial history of the Americas, "native gold and silver was quickly expropriated and sent back to Spain in fleets of gold- and silver-laden galleons", the gold and silver originating mostly from mines in Central and South America. Turquoise dated at 700 AD

5220-768: The mid-19th century, mining for minerals and precious metals, along with ranching , became a driving factor in the U.S. Westward Expansion to the Pacific coast. With the exploration of the West, mining camps sprang up and "expressed a distinctive spirit, an enduring legacy to the new nation"; Gold Rushers would experience the same problems as the Land Rushers of the transient West that preceded them. Aided by railroads, many people traveled West for work opportunities in mining. Western cities such as Denver and Sacramento originated as mining towns. When new areas were explored, it

5307-497: The mid-sixteenth century. On the continent, mineral deposits belonged to the crown, and this regalian right was stoutly maintained. But in England, royal mining rights were restricted to gold and silver (of which England had virtually no deposits) by a judicial decision of 1568 and a law in 1688. England had iron , zinc , copper , lead , and tin ores. Landlords who owned the base metals and coal under their estates then had

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5394-432: The minehead, where the water was stored in large reservoirs and tanks. When a full tank was opened, the flood of water sluiced away the overburden to expose the bedrock underneath and any gold-bearing veins. The rock was then worked by fire-setting to heat the rock, which would be quenched with a stream of water. The resulting thermal shock cracked the rock, enabling it to be removed by further streams of water from

5481-463: The mineral-rich material and extract the desired compounds and metals from the ore. Illegal mining Illegal mining is mining activity that is undertaken without state permission. Illegal mining is the extraction of precious metals without following the proper procedures to participate in legal mining activity. These procedures include permits and licenses for exploration of the land, mining and transportation.   Illegal mining can be

5568-431: The mining of previously impenetrable metals and ores. In 1762, one of the world's first mining academies was established in the same town there. The widespread adoption of agricultural innovations such as the iron plowshare , as well as the growing use of metal as a building material, was also a driving force in the tremendous growth of the iron industry during this period. Inventions like the arrastra were often used by

5655-522: The most respected writers of Goa. To cater to the needs of the Marathi speaking population, "Navprabha" was launched in 1970. It is a respected Marathi newspaper in Goa, with editorials, supplements and special issues. Dempo Shipbuilding and Engineering Pvt. Ltd., and Dempo Shipyard Pvt. Ltd. are the main companies in this sector. Another facility on the banks of river Zuari , in the name of Dempo Shipyard Pvt. Ltd., has been added to take advantage of

5742-405: The ore body. This leads to a mathematical resource estimation to estimate the size and grade of the deposit. This estimation is used to conduct a pre-feasibility study to determine the theoretical economics of the ore deposit. This identifies, early on, whether further investment in estimation and engineering studies is warranted and identifies key risks and areas for further work. The next step

5829-462: The ore concentrates, engineering concerns, milling and infrastructure costs, finance and equity requirements, and an analysis of the proposed mine from the initial excavation all the way through to reclamation. The proportion of a deposit that is economically recoverable is dependent on the enrichment factor of the ore in the area. To gain access to the mineral deposit within an area it is often necessary to mine through or remove waste material which

5916-442: The ore, lower wages, decreased occupational safety, benefits, and health standards for miners, and a lack of environmental protection measures. Artisanal miners often undertake the activity of mining seasonally. For example, crops are planted in the rainy season , and mining is pursued in the dry season . However, they also frequently travel to mining areas and work year-round. There are four broad types of ASM: Surface mining

6003-570: The overhead tanks. The Roman miners used similar methods to work cassiterite deposits in Cornwall and lead ore in the Pennines . Sluicing methods were developed by the Romans in Spain in 25 AD to exploit large alluvial gold deposits, the largest site being at Las Medulas , where seven long aqueducts tapped local rivers and sluiced the deposits. The Romans also exploited the silver present in

6090-412: The proper legal licenses. These operations are still illegal but it is not an indictable offence such as illegal mining operations organized by criminal groups.  Organized crime groups lead and control illegal mining activity in extremely rural areas where the state does not have full jurisdiction over the land.  Criminally organized illegal mining controls large-scale operations that violate all

6177-766: The rainforest. Illegal mining causes the deforestation of a protected rainforest. The use of mercury in illegal mining is contaminating the soil, water and air harming surrounding communities and the wildlife living in the forest. In Latin America, the illegal mining population is more likely to be infected with malaria since they are more vulnerable when they are ming deep in the rainforest. Illegal mining operations are often located in remote areas, making it more difficult to enforce mining standards . Furthermore, mining requirements can vary substantially from region to region, further complicating adherence with labor laws, environmental regulations, and tax legislation. Emissions of mercury originating in artisanal mining, most of which

6264-431: The remaining part of a coal seam previously exploited by other surface-mining techniques has too much overburden to be removed but can still be profitably exploited from the side of the artificial cliff made by previous mining. A typical cycle alternates sumping, which undercuts the seam, and shearing, which raises and lowers the cutter-head boom to cut the entire height of the coal seam. As the coal recovery cycle continues,

6351-446: The shafts could no longer be pumped dry with the available technology. Although an increased use of banknotes , credit and copper coins during this period did decrease the value of, and dependence on, precious metals , gold and silver still remained vital to the story of medieval mining. Due to differences in the social structure of society, the increasing extraction of mineral deposits spread from central Europe to England in

6438-567: The silver mines of Laurium , which helped support the Greek city state of Athens . Although they had over 20,000 slaves working them, their technology was essentially identical to their Bronze Age predecessors. At other mines, such as on the island of Thassos , marble was quarried by the Parians after they arrived in the 7th century BC. The marble was shipped away and was later found by archaeologists to have been used in buildings including

6525-474: The surface through the tunnels and shafts. Sub-surface mining can be classified by the type of access shafts used, and the extraction method or the technique used to reach the mineral deposit. Drift mining uses horizontal access tunnels, slope mining uses diagonally sloping access shafts, and shaft mining uses vertical access shafts. Mining in hard and soft rock formations requires different techniques. Other methods include shrinkage stope mining , which

6612-602: The tomb of Amphipolis. Philip II of Macedon , the father of Alexander the Great , captured the gold mines of Mount Pangeo in 357 BC to fund his military campaigns. He also captured gold mines in Thrace for minting coinage, eventually producing 26 tons per year. However, it was the Romans who developed large-scale mining methods, especially the use of large volumes of water brought to the minehead by numerous aqueducts . The water

6699-448: The top of a mountain off to reach ore deposits at depth. Most placer deposits, because they are shallowly buried, are mined by surface methods. Finally, landfill mining involves sites where landfills are excavated and processed. Landfill mining has been thought of as a long-term solution to methane emissions and local pollution. High wall mining, which evolved from auger mining, is another form of surface mining. In high wall mining,

6786-628: The top slats. Many examples of such devices have been found in old Roman mines and some examples are now preserved in the British Museum and the National Museum of Wales . Mining as an industry underwent dramatic changes in medieval Europe . The mining industry in the early Middle Ages was mainly focused on the extraction of copper and iron . Other precious metals were also used, mainly for gilding or coinage. Initially, many metals were obtained through open-pit mining , and ore

6873-469: The world's gold, followed by the establishment of large mines such as the Mount Morgan Mine , which ran for nearly a hundred years, Broken Hill ore deposit (one of the largest zinc-lead ore deposits), and the iron ore mines at Iron Knob . After declines in production, another boom in mining occurred in the 1960s. In the early 21st century, Australia remains a major world mineral producer. As

6960-474: The world, which was increasingly demanding copper for electrical and household goods. Canada's mining industry grew more slowly than did the United States due to limitations in transportation, capital, and U.S. competition; Ontario was the major producer of the early 20th century with nickel, copper, and gold. Meanwhile, Australia experienced the Australian gold rushes and by the 1850s was producing 40% of

7047-628: Was mined in pre-Columbian America; in the Cerillos Mining District in New Mexico , an estimate of "about 15,000 tons of rock had been removed from Mt. Chalchihuitl using stone tools before 1700." In 1727 Louis Denys (Denis) (1675–1741), sieur de La Ronde – brother of Simon-Pierre Denys de Bonaventure and the son-in-law of René Chartier – took command of Fort La Pointe at Chequamegon Bay ; where natives informed him of an island of copper. La Ronde obtained permission from

7134-576: Was primarily extracted from shallow depths, rather than through deep mine shafts. Around the 14th century , the growing use of weapons , armour , stirrups , and horseshoes greatly increased the demand for iron. Medieval knights , for example, were often laden with up to 100 pounds (45 kg) of plate or chain link armour in addition to swords , lances and other weapons. The overwhelming dependency on iron for military purposes spurred iron production and extraction processes. The silver crisis of 1465 occurred when all mines had reached depths at which

7221-406: Was still present near the surface in colonial times. Indigenous peoples used Lake Superior copper from at least 5,000 years ago; copper tools, arrowheads, and other artifacts that were part of an extensive native trade-network have been discovered. In addition, obsidian , flint , and other minerals were mined, worked, and traded. Early French explorers who encountered the sites made no use of

7308-411: Was the removal of water from mining shafts. As miners dug deeper to access new veins, flooding became a very real obstacle. The mining industry became dramatically more efficient and prosperous with the invention of mechanically- and animal-driven pumps. Iron metallurgy in Africa dates back over four thousand years. Gold became an important commodity for Africa during the trans-Saharan gold trade from

7395-403: Was used for a variety of purposes, including removing overburden and rock debris, called hydraulic mining , as well as washing comminuted , or crushed, ores and driving simple machinery. The Romans used hydraulic mining methods on a large scale to prospect for the veins of ore, especially using a now-obsolete form of mining known as hushing . They built numerous aqueducts to supply water to

7482-465: Was used. At other parts of the site, they penetrated the water table and dewatered the mines using several kinds of machines, especially reverse overshot water-wheels . These were used extensively in the copper mines at Rio Tinto in Spain, where one sequence comprised 16 such wheels arranged in pairs, and lifting water about 24 metres (79 ft). They were worked as treadmills with miners standing on

7569-539: Was usually the gold ( placer and then lode ) and then silver that were taken into possession and extracted first. Other metals would often wait for railroads or canals, as coarse gold dust and nuggets do not require smelting and are easy to identify and transport. In the early 20th century, the gold and silver rush to the western United States also stimulated mining for coal as well as base metals such as copper, lead, and iron. Areas in modern Montana, Utah, Arizona, and later Alaska became predominant suppliers of copper to

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