Peru seizes 4 tons of black market mercury bound for illegal gold mines

Peruvian authorities have halted a shipment of about four metric tons of mercury headed to Bolivia for presumed use in illegal gold mining, they said on Thursday, the latest sign of rising black market activity to fulfil soaring demand for the precious metal.

The mercury had been passed off as a container of crushed rock, but Peru's customs agency Sunat said an analysis revealed the material had been laced with mercury, a toxic metal subject to strict environmental controls.

“We could determine mercury was being transported in its natural state while camouflaged in shipments of gravel,” Sunat said.

The cargo was detected at the Callao port and came from Mexico, it said.

The seizure appears to be the largest on record in the Amazon region of South America where illegal gold mining is widespread, according to a review of past seizures by the Environmental Investigation Agency (EIA), a Washington-based advocacy nonprofit.

The biggest known shipment in the region, about a decade ago, was half the size, according to the EIA. The latest discovery comes as gold prices have soared in recent months, as global trade uncertainty has made gold particularly attractive for investors. Gold prices are up 28.5% so far this year and hit a record high of $3,500 (R61,764) per troy ounce in April. The frenzy for gold has led to deadly encounters from West Africa to Peru.

The EIA said it alerted Peruvian authorities to the shipment during its research into illicit mercury shipments from Mexico to Bolivia, Colombia and Peru, where miners use mercury to leach gold from sediment in the Amazon riverbanks.

It said higher mercury prices were driving illegal mercury production in Mexico, with a particular spike since the start of this year as traffickers paid a record $330 (R5,823) per kilogram.

“According to traffickers, gold miners' demand for mercury has driven the sophisticated operation and made it profitable,” the EIA said in a report released on Thursday.

It said its investigation showed 200 tons of mercury were smuggled from Mexico to Bolivia, Colombia and Peru between April 2019 and June 2025, accounting for a conservative estimate of $8bn (R141.1bn) in illegal gold.

Peruvian officials did not address the role of the EIA in the discovery of the mercury-laced gravel from Mexico.

Reuters