Instead, an estimated 12,000 workers, for the most part illegal workers from across the border in Brazil, roam the rivers in search of the precious metal, poisoning the rivers with the quicksilver they use to extract the gold.

Their method could not be more simple, or more brutal. From barges moored in the water, they pulverize the river banks with high-pressure hoses, pump out the resulting slurry and amalgamate the tiny specks of gold with quicksilver, or mercury.

Once the gold is extracted from the mercury, the highly toxic metal is dumped directly into the river along with the slurry.

"It is an ecological disaster," said Didier Kurtz, a gendarmerie official, who described the deforestation and environmental devastation left in the wake of the gold-washers.

This includes poisoning of the fish stocks, and consequently of the indigenous Indian population that depends on the fish as a dietary staple.

The gold trade has brought with it some other curses of development, including malaria, AIDS and various kinds of illegal trafficking.

Headless bodies turn up frequently in the forest. With an estimated 174,000 inhabitants, this department has the highest murder rate in France, with 51 killings in the first nine months of this year alone, most of them related to settlings of account between rival gangs.

Even though the police have kept up steady pressure on the illegal trade, entire villages -- complete with casinos, brothels and dentists -- have sprung up in the forest to serve the growing community of panhandlers.

"It's the Wild West," said gendarme captain Daniel Didnee, who commands a detachment of gendarmes checking traffic on the river in an attempt to halt supplies needed by the gold-extracting business, including large supplies of mercury. With the primitive methods in use, it can take 1.3 kilos (2.9 pounds) of quicksilver to process every kilo of gold, and it is estimated that at least 10 tonnes of mercury are released into the environment every year.

The impoverished Brasilian panhandlers, many living in conditions of virtual slavery, are the first victims of mercury vapor, which causes serious neurological defects. And according to a study carried out as long ago as 1997, more than half the Indians living along the river have excessive amounts of mercury in their organisms.

The use of quicksilver in gold prospecting adds to the 280 tonnes of mercury that the Bureau of Geological and Mining Research (BRGM) estimates to be locked in the soil, and which is being released into the air as the result of the intense traffic and movement caused by the gold rush.

Gold fever returned to French Guiana about 15 years ago, as pandhandlers began revisiting remote deposits along the Approague river that had been abandoned a century ago.

An earlier epoch produced gold exports officially totaling 207 tonnes, and the BRGM estimates that the department still has some 500 tonnes of reserves in minable depositions or in the alluvial soil deposited along the river banks.

Officially only 149 gold prospecting permits are in force, and last year exports totaling 3.2 million tonnes were declared officially. But that was undoubtedly only part if the whole. The customs service estimates that at least six tonnes left the country, and the regional industry directorate says that the gold smuggled out of the department may be two or three times more than the gold declared officially.

The authorities have sought to strangle the prospecting trade by making lightning raids on prospecting operations that are only accessible by pirogues, and by establishing blockades to halt supplies.

The primary task of the force of gendarmes here is to protect the space launching center at Kourou, and it was only two years ago that the police began mounting a serious challenge to the illegal prospectors.

Two specialized Anaconda squadrons with 75-men each were formed. But in total, the authorities have only 700 gendarmes and one helicopter to patrol 730 kilometers (450 miles) of frontier with Brazil and 520 kilometersmiles) with Surinam. In total, 95 percent of a territory the size of Portugal is covered by almost impenetrable forest.

They face a determined opponent equipped with helicopters, earth-moving equipment and communications radios. Some 250 police investigations are under way, in an attempt to discover the movers and shakers behind the prospecting activity.

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