Molybdenum and precious metal mineralization at Flammefjeld, Southeast Greenland

Metallogeny of Greenland

“…Platinum group minerals occur as inclusions in sulfides or as separate grains between silicates and consist of sperrylite, kotulskite (Pd(Te,Bi)) and moncheite while gold mostly forms monomineralic grains of native gold and electrum (Arnason et al, 1997a). Strong lithological control of the PGE mineralization suggests an orthomagmatic origin but local redistributed by post magmatic processes is possible (Arnason et al, 1997a;Andersen et al, 2002 Geyti and Thomassen (1983) The Flammefjeld igneous complex is slightly elongate covering an area of 500 x 800 m (Geyti and Thomassen, 1984). It consists of an intrusion breccia and younger quartz-feldspar porphyry and aplite that intruded syenite and basalt dikes (Geyti and Thomassen, 1984).…”

“…Strong lithological control of the PGE mineralization suggests an orthomagmatic origin but local redistributed by post magmatic processes is possible (Arnason et al, 1997a;Andersen et al, 2002 Geyti and Thomassen (1983) The Flammefjeld igneous complex is slightly elongate covering an area of 500 x 800 m (Geyti and Thomassen, 1984). It consists of an intrusion breccia and younger quartz-feldspar porphyry and aplite that intruded syenite and basalt dikes (Geyti and Thomassen, 1984). The quartz-feldspar porphyry forms a central pluton and concentric inward-dipping ring dikes in the periphery.…”

“…The quartz-feldspar porphyry forms a central pluton and concentric inward-dipping ring dikes in the periphery. Fragments of this rock type are found in the intrusion breccia (Geyti and Thomassen, 1984). The intrusion breccia is characterized by basal heterolithic aplite intrusion breccia with meter-scale angular to subrounded fragments, intermediate breccia dikes with very fine-grained quartz-K feldspar matrix and <20 cm-sized xenoliths and locally clast-supported upper igneous breccia with variable grain size (Geyti and Thomassen, 1984).…”

“…The igneous breccia hosts mineralized monzogranite and granophyre xenoliths. The mineralization forms stockwork that consist of molybdenite, pyrite, quartz and minor chalcopyrite with a quartz-sericite-pyrite and locally biotite alteration halo (Geyti and Thomassen, 1984). Quartz-carbonate veins with fluorite and barite and Pb-Zn-Cu-Ag-Au mineralization of 0.45g/t Au, 135g/t Ag, 0.58% Cu, 5.81% Pb and 1.35% Zn in hand specimen occur in the 5 km periphery of the Flammefjeld Igneous Complex (Thomassen and Krebs, 2001;Holwell et al, 2012b).…”

“…The mineralization is also characterized by enrichment in Mn, As, Sb, Mo and Bi (Thomassen and Krebs, 2001). The ore mineralogy is pyrite, galena, sphalerite, chalcopyrite, tertrahedrite, arsenopyrite and minor magnetite and hematite (Geyti and Thomassen, 1984). The generally <1 m wide veins typically have colloform, crustiform or cockade structures and vugs, indicating shallow emplacement.…”