"Big flotilla of illegal gold miners splits up in Brazil", 26 November 2021

...Hundreds of barges of illegal miners dredging for gold were navigating along the Madeira River in the Brazilian Amazon on Friday, and researchers said they posed a threat of pollution — including toxic mercury — for the broader environment...

Miner Thiago Bitencourt Gomes, wearing just a pair of shorts and some flip flops, told The Associated Press on Friday that about 400 barges – some 3,000 people – congregated in the area after one miner found gold there and alerted the others...

The wood-walled rafts, some equipped with satellite internet and air conditioning units, were tied together, forming rows of houses on the wide and muddy Madeira River, a large tributary that flows into the vast Amazon downstream from Manaus. Miners and their families live, eat and work on the barges, some accompanied by their dogs and other pets...

Environmentalists are alarmed by the fact miners use mercury to separate gold from the sediment they suck from the river bottom and the process gives off toxic vapors as well as spilling some into the river...

Miners told the AP on Friday that no authorities had come into contact with them. But fearing an operation, they left Autazes and continued along the river. The barges, pushed along by powerboats, headed off in different directions.

While local media reported tensions between the miners and residents of Autazes, journalists at the scene saw many locals taking advantage of the arrival of hundreds of visitors by selling food, electronics, diesel, clothes and even perfume...