The trail is named the Sendero de Oro after the gold miners who inhabit each terminus and we spent the first night in Los Mineros, a small rustic guesthouse that occupies a long low building that housed the bar, the whorehouse and the local jail in the mining heyday of Dos Brazos del Rio Tigre. Suzanne the proprietor and our gracious hostess has been in the area for decades and told stories about the rich history of the valley.
Fifty years ago this was the last frontier where most businesses on the peninsula had a scale on the counter so the miners could pay for their purchases with gold; now it’s all dollars or colones. As with most gold rushes the only ones who made consistent money were the merchants who transported and sold food, booze and tools.
There also used to be a strong market for mercury which was used to extract gold from ore, but now the miners themselves have prohibited this practice (it has always been illegal) because they’ve seen the effects of mercury poisoning on the rivers they live along and rely on.
Currently there are two main types of operations on the Osa, prospecting in the gravel riverbeds and small hand dug mines in the hillsides. In either case the gold is captured in the same way. Shovelfuls of earth or gravel are deposited into a “canoa” or sluice where rapidly running water in a narrow channel washes away the lighter dirt and rocks and a rough bottom traps the dense gold nuggets and flakes.
The canoa can be as simple as a small ditch dug in the mud and lined with Astroturf or a slightly more sophisticated and portable version consisting of a long metal tray with a panel of metal mesh on the bottom. Either way the sluice is filled one shovelful at a time so the environmental impact of these methods is relatively minor.
There are also a few old timers who still stand in the river scooping a couple of handfuls at a time into a pan then whirling it in a mesmerizing oscillation that lets the water wash away everything except the flakes of oro.