Scientific publications

The 1.89 Ga Välimäki massif is located in the northern Lake Ladoga area (Priladozhje). It is differentiated from wehrlites and pyroxenites to highly alkaline gabbro and diorites. Ilmenite-titanomagnetite ores confined to the pyroxenite portion of the massif form several bodies worked out as early as the 19th – early 20th century. High-grade titanomagnetite ores typically contain high concentrations of TiO2 (2.4–6.4 %), V2O5 (0.54–0.8 %) and MnO (0.16–0.3 %). Titanomagnetite with ilmenite disintegration lamellae contains 0.6–1 % V; Mn concentration in ilmenite is 1–1.87 % in the ores and up to 4.65– 6 % in disseminated mineralization in gabbro-diorites. Ores with disseminated-veinlet Cu-S-mineralization were found to contain noble metals such as Au, Pt and Pd (total concentration 0.3–1 g/t). Sulphides are represented by chalcopyrite and pyrite; sphalerite (Fe 6–9 %), pyrrhotite, argentopentlandite, galena, Se-galena, molybdenite, cobaltite and Ag-Bi-Te phases (hessite, stutzite, tellurobismuthite and tetradymite) are common. Minerals Pd and Pt – michenerite, froodite, merenskyite, Rh-sperrylite, and electrum, were revealed in the Välimäki massif for the first time.