The prosecution is one of the first in Brazil using the new technology to tackle clandestine trading that may account for as much as half of the gold output of Brazil, a major producer and exporter of the precious metal. Illegal gold mining has surged at thousands of sites in the Amazon rainforest, bringing environmental destruction and criminal violence to the region.
Seizures of illegally mined gold have surged seven-fold in the past seven years, according to Federal Police records obtained exclusively by Reuters.
Sandoval, who has been released pending trial and continues to preach with his wife at a Pentecostal Evangelical church in the central Brazilian city of Goiania, denies the allegations. He maintains there is no way to establish where the gold was mined once it is melted down into ingots for export.
"That’s impossible. To export gold one always has to melt it down," he told Reuters by telephone.
THE DNA OF GOLD
Historically, gold is notoriously difficult to trace, especially once metal from different sources has been melted together, erasing the original signatures. After that, it can easily be traded as a financial asset or be used in the jewelry industry.
But investigators say that’s starting to change. A police program called "Targeting Gold" is creating a database of samples from across Brazil that are examined with radio-isotope scans and fluorescence spectroscopy to determine the unique composition of elements.
The technique, long used in archaeology, was pioneered in mining by University of Pretoria geologist Roger Dixon to help distinguish between legal and stolen gold.
The program developed in partnership with university researchers includes the use of powerful light beams from a particle accelerator at a Sao Paulo lab to study nano-sized impurities associated with gold, be it dirt or other metals like lead or copper, that help trace its origins.
Humberto Freire, director of the Federal Police’s recently-created Environment and Amazon Department, said the technology allows scientists to analyze "the DNA of Brazilian gold."
"Nature has marked the gold with isotopes and we can read these unique fingerprints with radio-isotope scans," Freire said. "With this tool we can trace illegal gold before it gets refined for export."
The program has helped fuel an increase in gold seizures since leftist President Luiz Inacio Lula da Silva took office last year — up 38% in 2023 from 2022, according to government numbers seen by Reuters. New Brazil central bank gold market regulations, including mandatory electronic tax receipts for all trades and tightened monitoring of suspect transactions, have also helped, according to Freire.
"We estimate that around 40% of the gold that is extracted in the Amazon is illegal," he told Reuters. Brazil exported 110 tonnes of gold in 2020 worth $5 billion, according to official data, ranking among the world’s top 20 exporters. Last year, exports were 77.7 tonnes, a drop the government attributes to improved enforcement of illegal mining.
