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With few exceptions, podiform chromitites hosted in the mantle tectonite of the ophiolites are enriched in the less valuable IPGE (Os, Ir, and Ru) relative to more high-priced PPGE (Rh, Pt and Pd). Their chondrite‐nomalized patterns display negative slopes, with normalized values for Os, Ir and Ru exceeding those for Pt and Pd, up to 2 orders of magnitude. In agreement with this geochemical parameter, the most abundant PGM are sulphides of the laurite-erlichmanite serie, accompanied by minor Os-Ir-Ru alloys, arsenides and sulpharsenides. In this contribution, we present the results of a preliminary study of the Middle Arm Brook (MAB) ophiolitic chromitites, located in the Baie Verte Peninsula of Newfoundland (Canada) with special regard to their platinum group elements (PGE) geochemistry and mineralogy. The investigated chromitites occur as bands in serpentinized peridotite. The composition of chromite is homogeneous, with Cr# varying from 0.77 to 0.81, that corresponds to Cr2O3 contents between 55.4 and 57.9 wt%, and Al2O3 between 9.80 and 11.21 wt%. The Mg# is relatively low, from 0.51 to 0.59 corresponding to MgO contents between 10.3 and 12 wt%, and FeO between 15 and 20 wt%. TiO2 and Fe2O3 contents vary from 0.15 to 0.27 wt% and from 0.09 and 0.11 wt%, respectively. These values are very similar to those reported for a great number of mantle hosted chromitites, related with supra-subduction ophiolites. The MAB chromitites have peculiar PGE concentration, with relatively high total PGE (up to 1028 ppm). CI-chondrite normalized PGE patterns are variable. Some are flat, others show enrichment in PPGE relative to IPGE, which causes a positive slope. Among the PPGE, a strong positive anomaly of Pt is present in some samples (Fig. 1). These geochemical data are supported by the presence of a great variety of specific PGM containing all the six PGE. The PGM have size comprised between 1 and 20 μm. The majority of them form polyphasic grains composed of distinct PGM. According with their composition, the following PGM have been identified: laurite, osmium and ruthenium accompanied by a great number of unknown PGM such as Ir-S, Ir-Cu-S, Pt-Ni-Fe-Cu, Cu-Os-Ni-Pt, Rh-Pd-Sb and Pd-Rh-Sb. The PGM of the MAB chromitites have been found: 1) enclosed in fresh chromite and 2) in the silicate matrix and along cracks in contact with ferrian chromite, clinopyroxene, chlorite, serpentine and Ni-Fe alloys, possibly awaruite. Only laurite and an unknown Ir sulphide occur in fresh chromite as euhedral cystals, suggesting that these PGM were among the first minerals to crystallize at high magmatic temperature prior or concomitantly with the host chromite. Os, Pt, Rh and Pd bearing minerals always occur along cracks or in the silicate matrix. Most of these PGM are characterized by an irregular shape and some of them display a strong zonation (Fig. 2A, B). Several grains that contain Ru as the major element, with minor Os and Ir, form small blebs (about 1 μm) inside the Ni-Fe alloys (Fig 2C). These PGM are believed to represent the product of alteration of primary PGM and redistribution of PGE at low temperature. Magmatic precipitation of PPGE was possibly related with the segregation of an immiscible sulphide liquid precursor, that does not exist anymore, having been totally altered and desolphurized during serpentinization. Captions to figures: Fig. 1. PGE Chondrite-normalized patterns of MAB chromitites. Fig. 2. Back scattered electron images of PGM. A: Composite PGM in contact with ferrian chromite. B: PGM in contact with chlorite (black). The small PGM aligned along the tiny fissure are composed of Pd-Sb and Pt-Cu-Ni. C: Ni-Fe alloy (probably awaruite) containing two small inclusion of osmium (white spots), in contact with chlorite (black). 1 = Cu-Os-Pt-Pd, 2 = Rh-Pd-Sb, 3 = Pd-Rh-Sb, 4 = Pt-Ni-Fe-Cu. Scale bar is 10 μm.