IO – CG? Potential Critical Metals By-Product from Flotation Tails in Kaunisvaara, Sweden

Creating a Critical Metal by-product from an active mining operation is a sustainable way to enhance Europe's self-reliance on these metals without the need to open new mines. In this study, we investigate the presence of Au, Ag, and any Critical Metals (such as Co, Cu, or Ni) in the sulphide-rich flotation tailings at Kaunis Iron's Tapuli mine.
Kaunis' plant produces a magnetite concentrate using two magnetic separators. A newly installed flotation circuit extracts sulphides from the final product. The flotation tailings are therefore enriched in pyrrhotite, and---due to poor liberation in grinding---also pyrite and chalcopyrite to certain extents. Ingoing trace contents of e.g. Cu are enriched in the flotation tailings to potential ore-grade levels. Even grades below traditional ore grade in the tailings might be of economic interest hence converting the waste stream to a mineral resource.

Preliminary results include 2000 ppm Cu, 200 ppm Co, and 4 ppm Ag in the flotation tailings at a low sulphur feeding grade. Further sampling and assaying are underway, while ingoing sulphide content is steadily being increased.