The upper Neoproterozoic Mechanic Settlement Pluton, located in the Avalon terrane, southern New Brunswick, Canada, consists of alternating lenses of ...
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The Canadian Mineralogist Vol. 45, pp. 775-792 (2007) DOI : 10.2113/gscanmin.45.4.775
PLATINUM-GROUP MINERALS FROM THE MECHANIC SETTLEMENT PLUTON, SOUTHERN NEW BRUNSWICK, CANADA Tassos A. GRAMMATIKOPOULOS§ Department of Geology, Section of Earth Materials, University of Patras, Patras, 265 04, Greece
Sandra M. BARR, Russel S. HIEBERT and Cliff R. STANLEY Department of Geology, Acadia University, Wolfville, Nova Scotia B4P 2R6, Canada
Oleg VALEYEV SGS Lakefield Research Limited, 185 Concession St., PO 4300, Lakefield, Ontario K0L 2H0, Canada
Abstract The upper Neoproterozoic Mechanic Settlement Pluton, located in the Avalon terrane, southern New Brunswick, Canada, consists of alternating lenses of ultramafic through mafic to intermediate rocks. Known platinum-group element (PGE) mineralization occurs mostly in the ultramafic parts of the intrusion in association with Cu–Ni sulfides. The platinum-group minerals (PGM) are mainly Pd-dominated Pd–Te–Bi minerals; sobolevskite (PdBi) is most abundant, with rarer kotulskite, michenerite, moncheite, and froodite. Additional minerals identified are braggite, vysotskite, sperrylite, stillwaterite, hollingworthite, plumbopalladinite, Pt–Fe alloy, sopcheite, and paolovite. Sperrylite, Pt–Fe alloy, and braggite are the main carriers of Pt; Ir-, Os-, or Rubased PGM were not encountered. Gold and Au–Ag alloy are also associated with PGM. Most of the PGM occur as inclusions in silicate minerals (olivine, clinopyroxene and, less commonly, amphibole and phlogopite), or in sulfides (chalcopyrite, pentlandite, pyrrhotite and, less commonly, bornite and millerite), but also occur interstitially to the silicate and sulfide minerals. The size of the PGM ranges from
