1.1 Historical Context of Gold Mining in Latin America

Long before Columbus made landfall in the Americas, native societies were mining and decorating with gold. Gold artifacts dating as far back as 2,000 BC have been found in the Lake Titicaca Basin of Southern Peru.1 By the time the Spanish met the Inca in 1526, this practice had developed into a sophisticated tradition of casting, welding and plating.2 While still a display of power, gold in pre-Colombian societies was used largely for ceremonial and ornamental purposes. By contrast, for Europeans gold held monetary value and symbolized the prospect of individual and imperial mobility. Legends about gold fueled mania in European explorers, leading them into reckless journeys into remote regions and brutal clashes with Amerindian societies.

When Columbus arrived in the West Indies in 1492, he was on his way to Japan to find what Marco Polo had described as the island of “endless” gold.3 Encouraged by native ornaments and rumors of gold, Columbus wrote eagerly to Spain about the extravagant riches of the New World.4 Three decades later, Spanish conquistador Hernán Cortés would march into Tenochtitlan to sack the Aztec Empire’s treasury of gold artifacts, most of which were sent to Spain and melted into bullion.5 Meanwhile, the legend of El Dorado, originally the story of a chief who sprinkled gold into the waters of Lake Guatavita whenever he bathed, inspired dozens of expeditions into the interior of South America. Among the most famous were Conquistador Lope de Aguirre’s journey down the Amazon River, and Englishman Sir Walter Raleigh’s expedition to Guiana, both brutal tales of war and indigenous slaughter.6

Legends about gold fueled mania in European explorers, leading them into reckless journeys into remote regions and brutal clashes with Amerindian societies.

In spite of these extravagant and destructive quests, colonial gold mining in Spanish America yielded little return (silver extraction was considerably more lucrative).7 Latin America’s first large-scale colonial gold rush happened in Brazil, following the discovery of gold in the 17th century in the southeastern interior, a region still known today as Minas Gerais (General Mines). Thousands of Portuguese immigrated to the region, importing African slave labor and killing off local native tribes. Over 600 tons of gold were produced in Minas Gerais alone in the 18th century, making Portugal one of the richest European empires of the period.8

Although the flow of gold in today’s world works very differently than during colonial times, it is also a reiteration of a very old cycle. Not only does mining remain an industry that breeds desperation and violence, it also continues to serve the powerful at the peril of the vulnerable. In the case of the Amazon, that means neglected Brazilian immigrants in Suriname with malaria, impoverished miners in Venezuela extorted by guerilla groups, and indigenous tribe members, many of whom have been poisoned, killed and even enslaved for gold.

panning for gold

1.2 Large-Scale Gold Mining

Large-scale gold mining (LSGM) operations are mechanized with high capital investment and gold yields, and comparatively low labor intensity. While not always the case, large-scale mining operations typically meet national and international requirements, including the payment of royalties and taxes, the acquisition of mining permits, and compliance with health, safety, social, environmental, and mine closure standards.9 Of the officially reported, newly mined gold that enters the global market each year, 80% derives from LSGM facilities.10

While LSGM is typically more formalized and regulated than artisanal and small-scale gold mining (ASGM), it can still have several negative environmental and social impacts. In general, LSGM operations use open pit techniques and cyanide heap leaching to extract gold from the ore. These techniques require perpetual pollution monitoring even after mining operations end and consume large quantities of water and energy. Furthermore, LSGM often creates multi-story earthen dams that retain millions of cubic meters of mine tailings and are prone to collapse.11 An estimated 20 tons of waste rock, rock that has no economic value, are produced in LSGM operations to retrieve enough gold to produce one gold ring.12

An estimated 20 tons of waste rock, rock that has no economic value, are produced in LSGM operations to retrieve enough gold to produce one gold ring.

Finally, LSGM can push deforestation and community displacement well beyond the limits of its operating lease or concession, as it often results in land use displacement, urban expansion, development of commodity supply chains, and concerns over mine waste discharge and spills.13
gold mine
Photo by Tómas Munita

1.3 Artisanal and Small-Scale Gold Mining (ASGM)

Globally, 10-20 million people, including 4 to 5 million women and children, work directly in the artisanal and small-scale gold mining sector.14 Artisanal and small-scale gold miners are typically the poorest and most marginalized in society, and consequently often work outside the formal economy.15 ASGM produces about 20% of global gold output and contributes up to 90% of the gold mining workforce.16, 17 Consistent with the global gold rush over the past two decades, the number of artisanal and small-scale miners in Latin America has more than doubled in the last 15 years, reaching about 1.5 million individuals directly employed in the sector.18

The terms artisanal, small-scale, informal and illegal are often used interchangeably and inconsistently. According to Veiga (1997), the term “artisanal” refers to miners who use rudimentary methods (as opposed to conventional methods) but does not describe the size of the operation. However, other institutions may use the terms artisanal and small-scale to refer to the amount of ore processed. For example, the Peruvian government defines artisanal and small-scale as miners processing up to 25 tons per day (TPD) and 350 TPD respectively. Artisanal and small-scale gold miners often work illegally, because formalization is not financially or practically feasible. Illegal operations can be small-scale or heavily mechanized, with as many as thousands of hired workers and multi-million-dollar investment.19 Miners are also often said to work informally. In some contexts, this signifies that the miner is en-route to formalization but has not yet acquired legal license. In others, it means that miners operate outside the scope of any regulatory framework, but not in a way expressly prohibited by law.20 Finally, an informal miner may not have official state approval but may work in a manner unofficially sanctioned by the community or local authorities.21

Mineral wealth can be a valuable asset for sustainable development in regard to stimulating economic growth, and it has played a substantial role in many developing economies. In Guyana, for example, ASGM represents about 14% of total GDP.22 The World Bank and a number of development agencies view ASGM as an important source of economic development and poverty relief, noting that it can provide an alternative livelihood in rural areas.23 Nevertheless, the unregulated environment of informally-mined gold often leads to clandestine trading practices in which buyers do not pay tax to the gold-producing states and, therefore, the states miss out on important sources of revenue.

gold mining
Photo by Ron Haviv

1.4 Artisanal Mining Methods in the Amazon

Most artisanal and small-scale miners in the Amazon mine from alluvial gold (deposits found on land and in rivers and streams). Alluvial (or placer) mining varies greatly according to the local context, but typically involves some combination of hand panning, sluice boxes, heavy equipment, hydraulic mining, and dredging. In the Amazon region, miners commonly clear forest cover and then remove topsoil using machinery and high-pressure hoses to form a mining pit. The remaining mixture of gold-bearing soil and water, known as a “slurry,” is then passed down a sluice system, whereby the denser gold and fine-sediment (concentrate) are trapped.24 Miners may also work on barges (known as balsas or dragas) using dredges. This involves the use of hoses to suck sediment and water directly from the bottom of the water body, and then processing the gold using sluices or other equipment onboard the barge.25

Artisanal and small-scale miners typically use mercury to separate the gold, forming a mercury-gold amalgam. There are two ways of using mercury in gold mining: concentrate amalgamation, in which miners apply mercury after refining the ore with a concentration technique like those described above; and whole-ore amalgamation, in which miners apply greater quantities of mercury without prior concentration.26 While relatively uncommon in the Amazon, whole-ore amalgamation is considered by the Minamata Convention on Mercury as a worst practice, to be eliminated (the negative health and environmental effects of mercury contamination are described below).27 Once mercury is mixed with the gold-bearing sediment, the amalgam is then heated to vaporize the mercury and purify the gold. Although miners and gold shop owners occasionally use retorts, devices that capture mercury vapor and reduce losses by up to 95%, the more common practice is open-air burning of the amalgam, a technique that releases up to 50% of mercury into the environment.28

Photo by Tómas Munita

1.5 Mercury & Cyanide

When miners and owners of gold shops burn the mercury-gold amalgam, their families and communities directly inhale significant amounts of mercury vapor, which accumulates in the kidneys and brain. Mercury exposure can also cause miscarriages, respiratory failure, psychotic reactions, cardiovascular disease and even death.29

Mercury may also enter the local environment in its liquid state, where it can precipitate into ecosystems, poisoning rivers, fish and crops. Once in waterways, bacteria absorb mercury and transform it into methylmercury, an organic compound more toxic than inorganic mercury, which bioaccumulates up the food chain.30 31 Furthermore, miners and processors may use sodium cyanide to obtain residual gold from mercury-contaminated tailings (mining waste). When disposed of improperly, this process releases mercury-cyanide complexes into waterways, which are highly bioavailable and represent a significant threat to downstream aquatic life.32

It is important to note that ASGM is not the only factor to consider when assessing mercury in tropical ecosystems. Many areas in the Amazon have soils naturally enriched with mercury and processes such as geologic weathering, erosion from deforestation, biomass burning, plant transpiration and decomposition, and hydrological patterns all play an important role in the release and transport of mercury.33 34

1.6 Criminal Activity

In some cases, the informality and opacity of ASGM contributes to illicit activities. According to the Organization for Economic Cooperation and Development (OECD), ASGM cannot be considered legitimate when “it contributes to conflict and serious abuses associated with the extraction, transport, and trade of minerals.”35 Conflict and serious abuses include any form of cruel and inhuman treatment, any form of forced or compulsory labor, the worst forms of child labor, war crimes, and other gross human rights violations.36

Because gold holds high value in small amounts and is easily smuggled, it is a desirable resource for illicit groups. The informality and lack of transparency in ASGM enables corruption and criminal activity to flourish. Miners often have few options and are reliant on illicit groups to access materials and trade their product. This can further impede sustainable development, as once the miners are associated with criminal actors it can be more difficult to access the financial and legal means necessary to formalize. The combination of informality and extreme poverty create an environment where mining communities are vulnerable to violence, exploited or forced labor, and human trafficking.

The effects of criminal actors benefitting from ASGM are far reaching, threatening human security, the rule of law, good governance, and economic stability. In Colombia and Venezuela, where organized crime is strongly linked to illegal gold mining, narco-terrorist and guerilla groups have extorted miners in order to finance their operations.37 38 In Peru, criminal activities are less centralized, but violence, sex trafficking and forced labor are nonetheless widespread.39

Photo by Sam Abell

1.7 Protected Areas and Indigenous Peoples

In Latin America, illegal gold mining frequently occurs around protected areas, which typically have high conservation or cultural value. This is largely because by working in remote regions illegal miners can elude government enforcement. A 2015 study of gold mining sites in tropical forest regions of South America found that over 30% of total deforestation from gold mining occurred inside or within 10 km of 32 protected areas.40 A more recent report published by the World Resources Institute found that about 6% of total indigenous land in the Amazon (about 14,300,000 hectares) directly overlaps with active mining concessions or ongoing illegal mining activities.41

The World Resources Institute found that about 6% of total indigenous land in the Amazon (about 14,300,000 hectares) directly overlaps with active mining concessions or ongoing illegal mining activities.

Even when mining does not take place directly on their territory, indigenous peoples are often disproportionately affected by nearby mining activities because they are susceptible to the spread of disease and are typically more reliant on forest resources for survival. The accumulation of methylmercury in fish poses an especially large risk to indigenous people, as fish consumption tends to be an essential component of their diet. Numerous studies reveal elevated mercury levels in indigenous Amazon communities and fish consumption is widely believed to be the primary, though not exclusive, source of exposure.42 43 One review paper examined studies on 46 indigenous populations in the Amazon and found mercury exposures on average 7.5 times higher than background levels in the general population.44

One review paper examined studies on 46 indigenous populations in the Amazon and found mercury exposures on average 7.5 times higher than background levels in the general population.

In some cases, indigenous peoples will participate or profit from mining. This situation often results from a lack of economic alternatives, especially after mining has spread in the region and impacted natural resources.45 Whether or not indigenous people engage in mining, they often demand the expulsion of miners operating without consent on their land, as is the case with the campaigns of the Mundukuru46 and Yanomami47 in Brazil. Many indigenous people and other environmental activists who resist illegal mining face threats, violence, and even murder. A 2020 Global Witness report on killings of environmental defenders concluded that mining was the most dangerous sector in 2019, with 33 people murdered in the Amazon region alone, about 15% of the global total of killings.48

While agriculture and cattle ranching account for more total deforestation in the Amazon, the impact of Amazon gold mining is considered worse on a per hectare basis, due to its depletion of soil nutrients, deterioration of water quality, and transformation of riverways.

1.8 Land Degradation and Carbon Emissions

While agriculture and cattle ranching account for more total deforestation in the Amazon, the impact of Amazon gold mining is considered worse on a per hectare basis, due to its depletion of soil nutrients, deterioration of water quality, and transformation of riverways. Repeated soil disturbances and the formation of mining pools delays pioneer species growth and complete forest regeneration can take centuries.49 Furthermore, when miners use high-pressure hoses and pumps, they alter water flow patterns and increase sediment loads in rivers more than almost any other land-use activity, a process that degrades water quality and transforms underwater light fields.50 51

Amazon ASGM, particularly when unregulated, also contributes to climate change, as the Amazon rainforest is a crucial carbon sink that stores from 90-140 billion tons.52 One study, conducted in the Peruvian Amazon where illegal mining has been particularly severe, found that in 2017 over 1 million tons of carbon were released in the region of Madre de Dios, equivalent to the emissions of about 250,000 cars in an average year.53 Another study estimated that the slow regeneration of forests degraded by gold mining contributes about 21,000 tons of carbon per year, more than other land-use activities in the Amazon such as agriculture.54

gold mine
Photo by Ron Haviv

1.9 Malaria and Zoonotic Disease

Habitat destruction is a critical factor in the spread of infectious disease. Research suggests that deforestation and other land-use changes are responsible for up to 31% of emerging diseases.55 By pushing disease-carrying animals out of forests and closer to humans, deforestation increases the rates of zoonotic (animal-borne) infections, which account for up to 75% of emerging infectious diseases.56 Additionally, habitat destruction tends to weaken natural buffers to the spread of disease and strengthen disease vectors, such as mosquitoes. One study conducted in the Amazon found that increasing deforestation by 10% increased malaria cases by 3%, causing tens of thousands of cases (although malaria outbreaks have been shown to reduce clearcutting over time).57

ASGM can drive malaria transmission as it often leads to deforestation and abandoned mining pools that are optimal mosquito breeding grounds. Miners are susceptible to malaria because they work in dense clusters and have poor access to education and health services. Gold mining’s role in spreading malaria and other zoonotic diseases has become an increasing source of concern,58 particularly in light of the Covid-19 pandemic, and it has been studied in a number of Amazon countries.59 60 61


1 Aldenderfer et al., 2008
2 Cremers & Theiji, 2013
3 The Travels of Marco Polo/Book 3/Chapter 2, 2009
4 Jones, 2002
5 Día, 2008, p. 223
6 Drye, n.d.
7 Brown & Bakewell 2008, pp. 608-613
8 Eakin, 2008, pp. 606-608
9 World Gold Council, n.d.
10 Sieber & Brain, 2014
11 Moskowitz, 2014
12 Earthworks, n.d.
13 Sonter, et al., 2017
14 United Nations Environment Programme (UNEP), (n.d.)
15 Swenson and Domec 2011
16 Ibid
17 Fritz et al., 2018
18 USAID, 2019
19 Verité, 2016
20 UNEP, (n.d.)
21 IGF, 2017
22 World Bank, 2019
23 de Haan et al., 2020
24 USAID, 2019
25 USAID, 2019
26 UNEP, 2017
27 UN Environment, 2013
28 Veiga and Hinton, 2002
29 Agency for Toxic Substances and Disease Registry, 1999
30 Appleton et al., 1999
31 Harding et al., 2018
32 Marshall et al, 2020
33 Hacon et al., 2008
34 Veiga et al., 1999
35 Organization for Economic Cooperation and Development (OECD), 2013
36 Ibid
37 Financial Action Task Force & Asia/Pacific Group on Money Laundering, 2015
38 Testimony of Carrie Filipetti
39 Global Initiative against Transnational Organized Crime [GIATOC], 2016
40 Alvarez-Berríos & Aide, 2016
41 Vallejos et al., 2020
42 Ashe, 2012
43 Hacon et al., 2008
44 Basu et. al, 2018
45 Bristol, 2020
46 Angel, 2019
47 Branford, 2020
48 Wachenje, 2020
49 Peterson & Heemskerk, 20018 Eakin, 2008, pp. 606-608
50 Lobo et al., 2016
51 Lobo et al., 2017
52 Yale School of the Environment, n.d.
53 Csillik & Asner 2020
54 Kalamandeen et al., 2020
55 Kessler, 2018
56 Salyer et al., 2017
57 MacDonald & Mordecai, 2019
58 Langlois, 2020
59 Sanchez et al., 2017
60 Castellanos et al., 2016
61 Douine et al., 2018