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Illegal gold mining is on the rise in the tropical Andes. The Santiago-Cayapas watershed is located in the north of the Pacific basin of Ecuador, in the Chocó biogeographical region. It is recognized for its high biodiversity, as 62 fish species have been described in the area, and because it contains two of the largest protected areas in the …
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Gold is a highly required material for a wide range of personal and industrial applications. The high demand for gold, together with the shortage of natural resources and high pollution potential of wastes generated during mining and ore processing activities led to search for alternative sources of gold. A possible source is represented by mine …
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Researchers might start with the hypothesis that gold discoveries in an area lead to higher discount rates today, because gold mining rewards immediate …
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How M&A offers a shortcut to replacement of reserves. The BofA team said the deals announced last year more than replaced the reserves mined at Yamana Gold Inc (NYSE: AUY), Harmony Gold Mining Co ...
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The orthodox resource curse hypothesis suggests that countries encounter long-range trade-offs by electing to extract natural resources (e.g. minerals, oil and gas) at the expense of other potentially more sustainable alternatives (e.g. manufacturing, agriculture, service industries). ... The Porgera Gold mine in the highlands province of …
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Extracting gold from the mined ore creates a huge amount of waste — roughly 20 tonnes of mining waste to make a single 18-carat ring containing less than 10 grams of gold, according to an ...
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Gold, a report published by the U.S. Geological Survey, describes the main hypotheses geologists have proposed to explain the …
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One popular hypothesis proposes that many gold deposits, especially those found in volcanic and sedimentary rocks, formed from circulating ground waters driven by heat from bodies of magma...
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Gold mining has serious negative environmental impacts, especially due to pollution emanating from tailings storage facilities (TSFs, tailings dams, slimes dams). The most important forms of pollution from TSFs are acid mine drainage (AMD) and high levels of potentially toxic elements (PTEs). AMD arises from the high levels of pyrite in the …
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The mercury-free gold extraction method uses borax in the process of gold smelting. Borax is used in the smelting process because it lowers the melting point of gold and other metals. In this method, the mining of gold-bearing ore, the grinding of the mined material and the concentrating from sluicing are the same as in the amalgamation method.
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Due to the importance of the gold industry to the global economy, it is of great importance to investigate how gold mining companies make investment …
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Introduction. Gold mining represents a major threat to ecosystem integrity, including tropical rainforests that harbor the majority of global terrestrial biodiversity (Hammond et al., 2007; Kalamandeen et al., 2020).Artisanal gold mining, an increasingly prevalent land use across the Amazon Basin, results in fine-scale forest fragmentation …
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South African environmentalists have termed Acid Mine Drainage as the "single most significant threat to South Africa's environment" (Naidoo, 2009) and according to Dr Anthony Turton, formerly a scientist at the Council for Scientific and Industrial Research (CSIR) and the director of Touch Stone Resources—a company committed to …
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Worldwide there are over 43 million artisanal miners in virtually all developing countries extracting at least 30 different minerals. Gold, due to its increasing value, is the main mineral extracted by at least half of these miners. The large majority use amalgamation either as the final process to extract gold from gravity concentrates or from the whole ore. …
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Gold mining output and the real exchange rate are weakly exogenous variables in the system, with no feedback effects from gold mining to the real exchange rate. The impulse response analysis in Fig. 6 (c) is consistent with the long-run causality tests. The figure illustrates that the impulse responses of the real exchange rate with …
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Abstract. This article provides a comprehensive and chronological account of the technological advancements in alluvial gold mining. Gold has been a highly prized …
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The gold mining companies have been examined throughout the literature by focusing on their productivity growth level (Zheng and Bloch, 2014), ... This result supports our first hypothesis, implying during uncertainty, companies tend to postpone their investment (Sanderson et al., 2021). Each model indicates that ROA has a significant …
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The consumption of cyanide during processing operations is a major economic cost in the extraction of gold from its ores, while the discharge of cyanide wastes may result in significant environmental …
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VEIN-HOSTED gold deposits in low- to medium-grade metamorphic terrains are commonly associated with low-salinity hydrothermal fluids rich in CO 2 and/or CH 41–12. Fluid inclusion studies of gold ...
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The gold fields of the Witwatersrand Basin in South Africa are, by a landslide, the largest single gold producing district in the world. It has produced some 2 billion ounces over a century of mining and at an average grade of 15 g/t Au with a current head grade of 6-10 g/t Au and they still have estimated reserves of some 1,161 billion ounces ...
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Torex Gold is Mexico's second-largest gold producer, operating the Morelos gold property. Recently, the miner reported 358,780 ounces of gold produced through the end of Q3, putting it on track to ...
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The California Gold Rush. On January 8, 1848, James W. Marshall, overseeing the construction of a sawmill at Sutter's Mill in the territory of California, literally struck gold. His discovery of trace flecks of the precious metal in the soil at the bottom of the American River sparked a massive migration of settlers and miners into California ...
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Gold mining in Ecuador has been present in the country since Inca times; over the years interest in the mineral has increased, leading to the creation of legislation to control the mining sector in a safe manner. The Litoral region consists of seven provinces, six of which have registered gold concessions; the most affected provinces are El Oro …
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The results in Table 2 suggest that the assumption of independence is violated for returns on the gold mining INDEX, fluctuations in the exchange rate and returns on the JSE All Share Index. This is somewhat unexpected; financial data is widely assumed to be serially uncorrelated (see Cont 2001). 5 This violation can be attributed to the …
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The Beta-Hunt gold mine discussed above is a good example of this; other good examples include the most significant ore shoot at the Telfer Main Dome deposit, which forms at the boundary between a massive quartzite and a carbonate unit (unpublished company data; see Fig. 4); the Ora Banda gold camp, where high-grade deposits form …
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On the Dominican side of the island, two of the world's largest mining companies have teamed up to build a $3.1 billion gold mine that will reach full production this year. Now, other mining companies working in Haiti are buying up permits to explore more than half of the country's mineral-rich north. Following centuries of deforestation and …
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This paper studies the dynamic relationship between gold, crude oil, US dollar index and volatility index (VIX). • The price returns of crude oil, VIX have a positive impact …
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Abuakwa's traditional gold mining of some 600 years ago. Like traditional gold mining, galamsey has strong cultural ties to the land; many operators use techniques almost identical to those of their ancestors. Their operations feature technology that rarely extends beyond the pickaxe (asɔsɔ) (Dumett 1987).
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Innovation plays a critical role in the mining industry as a tool to improve the efficiency of its processes, to reduce costs, but also to meet the increasing social and environmental concerns among communities and authorities. Technological progress has also been crucial to allow the exploitation of new deposits in more complex scenarios: …
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A brief history of gold uses, prospecting, mining and production. Republished from a USGS general interest publication by Harold Kirkemo, William L. Newman, and Roger P. Ashley. Egyptian gold: Artisans of ancient civilizations used gold lavishly in decorating tombs and temples, and gold objects made more than 5,000 years ago have been found in ...
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