New methods help the mining industry uncover hidden metal deposits

Metals such as zinc and copper are essential to the green transition – yet new deposits are becoming increasingly difficult to find. In his doctoral thesis, Jonathan Jose Rincon Gamero at Luleå University of Technology shows how advanced mineral analysis can help the mining industry discover hidden resources and use raw materials more efficiently.

“It’s not only about finding the metal, but also about understanding how it has moved through the Earth’s crust and how we can extract it more efficiently,” says Jonathan Jose Rincon Gamero, researcher in Ore Geology at Luleå University of Technology.

New clues from the Skellefte District

In his thesis Textural and chemical characterization of sulphide minerals for improved beneficiation and exploration, Skellefte district, Sweden, he examines how sulphide minerals in the classic mining region of the Skellefte District have been shaped and transformed by geological processes. Focusing on the Rävliden North deposit, he traces how metals and mineral structures have evolved through heat, pressure and deformation over billions of years.

By combining textural analysis, mineral chemical studies (including trace element and isotopes), Jonathan Rincon demonstrates that certain minerals retain chemical fingerprints of their original formation and subsequent spatial mobilization, and through mineral processing tests he further shows what happens during metal concentration – information that can guide exploration towards new, hidden deposits and inform mineral processing engineers about optimization and by-product possibilities, such as critical raw materials.

“By understanding how trace elements respond to pressure and temperature during metamorphism over geological time, we can get better at finding ores. Moreover, by doing detailed characterization of the ores, we enable sustainable extraction possibilities such as efficient mineral concentration and by-product opportunities” he says.

Knowledge for sustainable exploration

The results are particularly valuable for future exploration and resource efficiency. They show that even strongly metamorphosed ores can preserve geochemical signatures that can be used as hints towards new undiscovered metal concentrations. This knowledge can help with exploration targeting, with the potential to reduce both costs and environmental impact.

The research also demonstrates that besides silver, small amounts of critical metals to the EU such as antimony and bismuth are present in these ores. This opens the possibility of investigating whether they could be economically recovered as by-products during zinc and copper beneficiation—potentially offering both economic and environmental benefits.

Strengthening Europe’s raw-material security

Funded by Boliden and the Geological Survey of Sweden (SGU), the work exemplifies how collaboration between academia and industry can strengthen Sweden’s mining sector and support the EU’s strategy for securing critical raw materials – a key challenge for the green transition.

“The mining industry needs new knowledge to find and process metals more sustainably. This research deliver the insights needed to make that possible,” says Jonathan Jose Rincon Gamero.