{"id":3516,"date":"2016-12-01T08:37:03","date_gmt":"2016-12-01T08:37:03","guid":{"rendered":"http:\/\/webfe10.fe.cpd.local\/caribbeanlithos\/?p=3516"},"modified":"2026-03-04T15:32:38","modified_gmt":"2026-03-04T15:32:38","slug":"2016-fibrous-platinum-group-minerals-in-floating-chromitites-from-the-loma-larga-ni-laterite-deposit-dominican-republic","status":"publish","type":"post","link":"https:\/\/caribbeanlithos.ub.edu\/?p=3516","title":{"rendered":"2016: Fibrous Platinum-Group Minerals in \u201cFloating Chromitites\u201d from the Loma Larga Ni-Laterite Deposit, Dominican Republic"},"content":{"rendered":"<p><strong>Fibrous Platinum-Group Minerals in \u201cFloating Chromitites\u201d from the Loma Larga Ni-Laterite Deposit, Dominican Republic<\/strong><\/p>\n<p><u>Abstract<\/u><\/p>\n<p>This contribution reports on the observation of enigmatic fibrous platinum-group minerals (PGM) found within a chromitite body included in limonite (\u201cfloating chromitite\u201d) from Ni-laterites in the Dominican Republic. Fibrous PGM have a Ru-Os-Ir-Fe dominated composition and are characterized by fibrous textures explained by grain-forming fibers which are significantly longer (1\u20135 _m) than they are wide (~100 nm). Back-scattered electron (BSE) images suggest that these nanofibers are platinum-group elements (PGE)-bearing and form &lt;5 _m thick layers of bundles which are oriented orthogonal to grains\u2019 surfaces. Trace amounts of Si are most likely associated with PGE-bearing nanofibers. One characteristic fibrous PGM was studied in detail: XRD analyses point to ruthenian hexaferrum. However, the unpolished fibrous PGM shows numerous complex textures on its surface which are suggestive for neoformation processes: (i) features suggesting growth of PGE-bearing nanofibers; (ii) occurrence of PGM nanoparticles within film material (biofilm?) associated with PGE-bearing nanofibers; (iii) a Si-rich and crater-like texture hosting PGM nanoparticles and an Ir-rich accumulation of irregular shape; (iv) complex PGM nanoparticles with ragged morphologies, resembling sponge spicules and (v) oval forms (&lt;1 _m in diameter) with included PGM nanoparticles, similar to those observed in experiments with PGE-reducing bacteria. Fibrous PGM found in the limonite may have formed due to supergene (bio-)weathering of fibrous Mg-silicates which were incorporated into desulphurized laurite during stages of serpentinization.<\/p>\n<p><strong>Keywords:<\/strong> PGE; PGM; fibrous; nanofibers; Ni-laterite; supergene; weathering; neoformation; Falcondo; Dominican Republic<\/p>\n<p>----------------------------------------------------------------------------------------------------------<\/p>\n<p><strong>To Cite this article:<\/strong> Aiglsperger, T., Proenza, J.A., Longo, F., Font-Bardia, M., Gal\u00ed, S., Roqu\u00e9, J., Baurier-Aymat, S. (2016): Fibrous Platinum-Group Minerals in \u201cFloating Chromitites\u201d from the Loma Larga Ni-Laterite Deposit, Dominican Republic. <em>Minerals<\/em>, 6(4)-126, 1-11.<\/p>\n<p><strong>DOI<\/strong>: <a href=\"http:\/\/www.mdpi.com\/2075-163X\/6\/4\/126\">10.3390\/min6040126<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"Fibrous Platinum-Group Minerals in \u201cFloating Chromitites\u201d from the Loma Larga Ni-Laterite Deposit, Dominican Republic Abstract This contribution reports on the observation of enigmatic fibrous platinum-group minerals (PGM) found within a chromitite body included in limonite (\u201cfloating chromitite\u201d) from Ni-laterites in the Dominican Republic. Fibrous PGM have a Ru-Os-Ir-Fe dominated composition and are characterized by fibrous textures explained by grain-forming fibers&nbsp;<a href=\"https:\/\/caribbeanlithos.ub.edu\/?p=3516\" class=\"read-more\">Continue Reading<\/a>","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[51,42,44],"tags":[],"class_list":["post-3516","post","type-post","status-publish","format-standard","hentry","category-publications2016","category-dominicanrepublic","category-publications","cat-51-id","cat-42-id","cat-44-id"],"_links":{"self":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3516","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3516"}],"version-history":[{"count":1,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3516\/revisions"}],"predecessor-version":[{"id":3517,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=\/wp\/v2\/posts\/3516\/revisions\/3517"}],"wp:attachment":[{"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3516"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3516"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/caribbeanlithos.ub.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3516"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}