Brazil is using forensic science to tackle illegal gold mining in the Amazon, a top threat to the rainforest, Indigenous groups and other communities there that has accelerated deforestation and driven mercury contamination to dangerous levels. This was reported by Qazaqyia.kz citing Associated Press.
The work takes place at the National Institute of Criminalistics in Brasilia, the country's capital, where federal police have set up a "gold lab" that collects and analyses samples from across the country.
The objective is to determine if a newly acquired sample — gold seized in a police raid, for example — comes from a protected area, meaning it has been illegally mined. It's called "gold fingerprinting" — tracing the origin of gold samples with high precision.
At the lab, sparkling gold flakes are kept in tiny, coin-shaped vessels, but the most valuable thing about them is the data they hold. Each speck is unique because while it forms in nature, inside a rock or a riverbed, the gold deposits absorb particles from the area, such as traces of silver and copper.
And that's the fingerprint. It allows the investigators to determine if gold seized during a police raid was actually mined in the area its purported owner claims it came from, or if it was illegally sourced from a national forest or Indigenous land — in which case its analysis would match stored data from the protected area.
Gustavo Geiser, a federal police forensics expert, says the method has been developed since 2019 in collaboration with Brazilian universities. The investigators use tools such as X‑ray fluorescence spectrometry, scanning electron microscopy and laser ablation mass spectrometry.
"As we advanced, the forensic examinations became increasingly complex," Geiser said, but the question before them was always the same: "Where did this gold come from?"
If the forensics prove a gold sample was illegally mined, the information then helps police build a case and move forward with further investigations and possibly charges.
Those involved in environmental crimes in the Amazon frequently resort to fraud to introduce their goods into legal markets, not just gold but also timber.