Record-high global gold prices are fueling a renewed illegal mining surge across Brazil’s Amazon rainforest, accelerating deforestation in protected conservation zones and driving mercury contamination to hazardous levels. Officials, environmental scientists, and federal prosecutors say global demand for gold as a safe investment asset, combined with weaknesses in Brazil’s mineral export control system, is financing an extraction boom that threatens Indigenous communities and vital waterways.
While mining accounts for a relatively small fraction of the Brazilian Amazon’s overall annual clearing compared to agricultural expansion, it has become the dominant driver of ecological destruction inside specific protected reserves and Indigenous lands. Environmental monitoring organizations warn that the rapid, concentrated expansion threatens the rainforest’s capacity to regulate regional rainfall and global temperature patterns.
A study released Tuesday by the nongovernmental organization Amazon Conservation, in partnership with Brazilian nonprofit Instituto Socioambiental, found illegal mining sites driving clear-cutting inside three conservation areas in the Xingu region, one of the world’s largest expanses of protected forest. The Terra do Meio Ecological Station recorded its first cases of illegal mining in the reserve in September 2024, and by the end of 2025, mining-related deforestation there had spread to 30 hectares, or 74 acres. At the Altamira National Forest, illegal mining accumulated 832 hectares, or roughly 2,056 acres, of deforestation between 2016 and September 2025. A new mining front that opened in the forest in 2024 had expanded to 36 hectares by October 2025, accounting for nearly half of the mining-related deforestation recorded in the unit that year.
Satellite monitoring also detected a clandestine airstrip used to transport personnel and supplies at the Nascentes da Serra do Cachimbo Biological Reserve. Illegal mining inside that reserve grew from just 2 hectares, or 5 acres, to at least 26.8 hectares, or 66 acres, in 2025. “What makes mining particularly problematic is that it targets protected areas and Indigenous territories,” said Matt Finer, director of Amazon Conservation’s Monitoring of the Andes Amazon program.
In 2023, Amazon Conservation partnered with Earth Genome and the Pulitzer Center to develop the Amazon Mining Watch, a platform that uses satellite imagery to track mining activity across the Amazon basin since 2018. The platform’s data shows roughly 496,000 hectares, or 1,225,640 acres, of rainforest have been cleared for mining across the region since then, including approximately 223,000 hectares in the Brazilian portion. Amazon Conservation estimates that 80% of mining-related deforestation in Brazil carries a high risk of occurring illegally, as most forest clearing for extraction lacks proper permits or occurs inside legally protected boundaries.
Mining remains a relatively small driver of deforestation nationwide compared to agricultural expansion and cattle ranching. Official Brazilian data show approximately 579,600 hectares, or roughly 1.4 million acres, of the Amazon were cleared in 2025, with mining accounting for about 17,000 hectares, or 42,000 acres. Targeted enforcement has successfully slowed destruction in isolated areas, such as a major 2023 federal crackdown on illegal gold mining in the Yanomami Indigenous territory along the Venezuelan border. Annual growth in newly mined areas inside the Yanomami territory fell sharply following that intervention, and nearly all of the 5,500 hectares of deforestation documented inside the territory had occurred prior to 2023.
Despite these targeted victories, localized enforcement has not curbed illegal mining across the broader Amazon basin. When federal authorities destroy dredges and processing equipment in one region, miners routinely relocate deeper into protected zones or resume operations once enforcement teams depart. “Last year, I took part in an operation that destroyed more than 500 dredges on an Indigenous land,” said federal prosecutor André Luiz Porreca, who investigates illegal mining in the western Brazilian Amazon. “The following week, Indigenous people showed me photos proving the miners had already returned.” Porreca described enforcement in the region as a “cat-and-mouse game” that struggles to permanently displace organized extraction networks.
Porreca said illegal gold mining operations are directly financed by Brazil’s largest criminal organizations, including the Red Command and the First Capital Command. The groups operate in approximately a third of the municipalities across the Brazilian Amazon and provide the capital necessary to purchase industrial extraction equipment. “They have the money to bankroll these operations,” Porreca said, noting that heavy-duty river dredges can cost as much as 15 million reais each. While enforcement significantly eased pressure in the Yanomami territory, illegal mining has intensified across Indigenous lands in the Xingu River basin. The most critical situation is concentrated on the Kayapo Indigenous land, where roughly 7,940 hectares of rainforest have been cleared by illegal mining operations, making it the largest single site of mining-related deforestation in the Brazilian Amazon.
“It’s basic market logic. With more buyers, there are more people exploiting gold,” Porreca said, pointing to record-high metal prices as the primary economic driver. He noted that Brazil’s mineral export control system remains weak, allowing laundering schemes that wash illicit gold into commercial supply chains and give it the appearance of legal market origin.
The environmental damage extends well beyond canopy loss. Illegal mining operations routinely dump toxic mercury into river systems to separate gold ore from sediment, contaminating waterways and causing the toxin to accumulate in fish consumed by riverside and Indigenous communities. In April, Porreca submitted a report to the Inter-American Commission on Human Rights detailing the widespread mercury contamination in the region. The report cited a study by Fiocruz, a state-run medical research institution, which found that 21.3% of fish sold in public markets across the Amazon exceeded mercury consumption limits set by the World Health Organization. The Fiocruz study found children ages 2 to 4 in affected areas were consuming mercury at levels up to 31 times higher than the recommended maximum threshold.
Under Brazilian law, all commercial mining is strictly prohibited on Indigenous lands. The Ministry of Indigenous Peoples said in a statement that combating illegal mining incursions on those territories is a priority for President Luiz Inácio Lula da Silva’s administration. The ministry stated that the invasions are sustained by sophisticated criminal networks and that effectively stopping them requires dismantling the external economic and logistics chains that support them. The Ministry of Environment acknowledged that mercury contamination from illegal gold mining remains a persistent public health crisis in the region, adding that the agency is expanding scientific water monitoring while supporting ongoing federal enforcement operations. Brazil’s Federal Police did not respond to requests for comment from The Associated Press.