But it's not gold they returned with – it's a collection of seeds and cuttings from rare and threatened plants and trees.
The expedition was organised by the iCONic Project, a conservation programme backed by the Perthshire Big Tree Country initiative and with the involvement of the Royal Botanic Garden Edinburgh (RBGE).
During their month-long trip, the team collected seeds and herbarium material including the Chilean plum yew and the ruil, which are among the world's most threatened species.
Project leader Tom Christian and Martin Gardner, an expert in conifer conservation from the RBGE, say the samples mean the difference between extinction and survival for these plants and trees.
"Many of these species are on the brink of extinction, just clinging to life in tiny fragments of forest," says Christian, adding that he saw some species "which are highly unlikely to still be there in 100, maybe even 50 years' time".
The Scottish experts say it is Chile's lacklustre approach to conservation which has caused many of the problems they are trying to overcome.
The country has suffered extreme deforestation, with tens of thousands of square miles of natural vegetation cleared to make way for commercially-viable North American pine.
"The damage that was done to Chile's coastal Cordillera forest, which started in the 1970s, was unprecedented," says Martin. "The area destroyed represents one of the most rapid losses of temperate rainforest anywhere in the world.
"It's so important that these tiny fragments of forest which remain are preserved for the benefit of future generations."
Chile is also engaged in an extensive programme of building hydro-electric dams, one of which is scheduled to flood the San Fabian Alico valley in 2015, threatening the existence of the plum yew population.
The team visited the valley to collect seeds and met local residents.
"There's obviously very strong local opposition to the dam," says Christian. "We met people in their seventies who have lived there all their lives, they don't want to leave. The natural environment in the valley is extraordinary, very rich in species. It's just extraordinary to think it will all be wiped out."
In Edinburgh, the seeds collected will be propagated at RBGE and grown for about three years before they are relocated – some of them to a range of selected sites within Perthshire, acting as a repository for Chile to draw on in the event the species are wiped out entirely.
The RBGE has thorough quarantine and screening procedures in place to ensure the plant material it produces is healthy and free of pests and diseases.