Mineralogical-geochemical indices of the Pitkaranta ore district specialization for rare and precious metals
Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2016. V. 145. N 2. P. 74-95
The modern high-precision investigation techniques have allowed to reveal in skarn deposits of Pitkäranta ore district, connected with Salmi anorthosite-rapakivi granite massif, about 140 ore minerals, among them 58—for the first time. 25 minerals (roquesite, angelaite, pavonite, cervelleite, yalpaite, etc.) have become the very first finds in the Karelia-Kola region. Presence in Pitkäranta ores of roquesite (CuInS2), indium-bearing sphalerite (with up to 1.0 % In), gold, an assemblage of silver, bismuth and tellurium minerals has the most important metallogenic meaning. Therefore, the Pitkäranta ore district may be considered as the most perspective area for indium in Russia. It needs the supplementary exploration, with reassessment of known deposits. High prospects for the platinum group mineralization are confirmed by the high palladium grade in Riphean sandstones (up to 4 ppm) formed from the source of Salminsky anorthosite-rapakivi complex.
Key words: Pitkäranta deposits, skarns, minerals of gold and silver, platinoids, indium, roquesite, indium-bearing sphalerite, metallogeny, Karelia.