GOTHENBURG, Sweden—Sweden is home to the world’s largest open drill-core archive, and it is a center of activity for amateur “mineral hunters.” The mineral-rich country has an unusual crowdsourcing approach to charting its mineral assets.
At the Mineral Resources Information Office in northernmost Sweden, all citizens, as well as foreign prospectors, can access maps and drill cores gathered from government surveys. The office is part of the Geological Survey of Sweden (SGU), which began operations in 1858 and has thus generated a wealth of material.
Geologist Johan Soderhielm says that this type of archive exists in Norway and Finland as well, “but there is no archive of this size anywhere else in the world.”
The Mineral Resources Information Office is located in an area known for its rich deposits of base metals and gold. The drill core archive contains samples from almost 19,000 holes, the oldest dating from the late 19th century.
All of these cores belong to the Swedish government—in other words, to the Swedish people—so the idea is that all citizens should have access to them, Soderhielm said.
Sweden has a long history of mining and export of minerals and metals, with the first mining organization forming in 1637. In 1992, the Swedish government decided to attract foreign investors by allowing them to do the prospecting.
If a company is interested in a certain mineral, it can investigate samples from any area of Sweden instead of getting its own samples. A company can take part of the core out of the country for analysis. The only requirement is that it send the results back to the archive, where they become available to the general public.
Hobby Mineral Hunters
But it’s not only experts searching the open mineral archives.
Amateur mineral hunters come in all ages, said Leif Blidstrom of SGU. He is responsible for the SGU mineral hunt competition, Mineraljakten.
“I have had two mineral hunters who were older than 90 years old send me samples,” he said.
The competition used to run only in northern Sweden, but this year it will be open to all of Sweden. Participants must be amateurs, however. Blidstrom has not heard of a similar competition anywhere else in the world.
“We are certainly at least the competition with the broadest range of participants. Youths and children can also participate,” he said.
The hunters send in rock samples they think could be of interest. SGU has found in the past that some 10 percent are worth further analysis. Blidstrom visits the sites of the most interesting discoveries.
“This way, we can see what the area [where the sample was found] actually looks like. Many times, the mineral hunters have not found the best sample out there,” he said. Blidstrom assesses whether there might be more of the mineral in the region.
Further analysis has sometimes yielded surprising results. Gold can be found in a type of rock where it is not expected, and rare earth metals can also show up in analysis, since they are not visible to the naked eye.
Mineral hunters have identified areas that can actually be exploited, especially when it comes to rock types like marble and quartz. Such finds have already generated job opportunities, but the competition entries also provide much valuable information.
“The people in their late seventies are great,” Blidstrom said. “When fall comes around and I’m planning my site visits, they are already planning for next year. They never sit still!”
