Applied Mineralogy and Mineral Processing of the Disseminated Cu-Ni-PGE Ore from the Keivitsa Deposit

• Main Authors: Sodankylä Northern Finland, S. Luukkanen, R. Kalapudas, J. Laukkanen, K. Kojonen
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: late 2004 by Scandinavian Gold Ltd; for; Sodankylä; Northern Finland
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.551.4301; http://arkisto.gtk.fi/ej/ej49/ej49_pages_170_173.pdf

ABSTRACT. Disseminated sulphide ore samples in drill core from the Keivitsa Ni-Cu-PGE deposits, Sodankylä, Northern Finland, were studied mineralogically and mineral processing tests were made. The disseminated ore tends to be fine-grained (74 % within the size range 250-2500 μm) and consists of troilite and hexagonal pyrrhotite, magnetite, pentlandite and chalcopyrite as intercumulus phase in altered and sheared clinopyroxenite and lherzolite. The PGM comprises palladian melonite, moncheite, merenskyite, and sperrylite, which occur both inside sulphides and at sulphide grain boundaries. The ore assays are: Ni 0.26%, Cu 0.36%, Au 0.13-0.16 g/t, Pt 0.2-0.3 g/t and Pd 0.18-0.21 g/t. The MgO-rich silicates are weakly altered and contain abundant magnetite inclusions. Removal of magnetite and magnetite bearing Mg-silicates by magnetic methods before flotation was recommended. The ore feed was crushed and milled with a ball mill and tested for rougher and cleaning flotation, producing a sulphide concentrate carrying Cu 6.1%, Ni 4.4 % and Au+Pt+Pd 1.03 g/t. 1