TY - JOUR A1 - Zozulya, Dmitry R. A1 - Kullerud, Kare A1 - Ribacki, Enrico A1 - Altenberger, Uwe A1 - Sudo, Masafumi A1 - Savchenko, Yevgeny E. T1 - The newly discovered neoproterozoic aillikite occurrence in Vinoren (Southern Norway) BT - age, geodynamic position and mineralogical evidence of diamond-bearing mantle source JF - Minerals N2 - During the period 750-600 Ma ago, prior to the final break-up of the supercontinent Rodinia, the crust of both the North American Craton and Baltica was intruded by significant amounts of rift-related magmas originating from the mantle. In the Proterozoic crust of Southern Norway, the 580 Ma old Fen carbonatite-ultramafic complex is a representative of this type of rocks. In this paper, we report the occurrence of an ultramafic lamprophyre dyke which possibly is linked to the Fen complex, although Ar-40/Ar-39 data from phenocrystic phlogopite from the dyke gave an age of 686 +/- 9 Ma. The lamprophyre dyke was recently discovered in one of the Kongsberg silver mines at Vinoren, Norway. Whole rock geochemistry, geochronological and mineralogical data from the ultramafic lamprophyre dyke are presented aiming to elucidate its origin and possible geodynamic setting. From the whole-rock composition of the Vinoren dyke, the rock could be recognized as transitional between carbonatite and kimberlite-II (orangeite). From its diagnostic mineralogy, the rock is classified as aillikite. The compositions and xenocrystic nature of several of the major and accessory minerals from the Vinoren aillikite are characteristic for diamondiferous rocks (kimberlites/lamproites/UML): Phlogopite with kinoshitalite-rich rims, chromite-spinel-ulvospinel series, Mg- and Mn-rich ilmenites, rutile and lucasite-(Ce). We suggest that the aillikite melt formed during partial melting of a MARID (mica-amphibole-rutile-ilmenite-diopside)-like source under CO2 fluxing. The pre-rifting geodynamic setting of the Vinoren aillikite before the Rodinia supercontinent breakup suggests a relatively thick SCLM (Subcontinental Lithospheric Mantle) during this stage and might indicate a diamond-bearing source for the parental melt. This is in contrast to the about 100 Ma younger Fen complex, which were derived from a thin SCLM. KW - aillikite KW - phlogopite KW - carbonate KW - spinel KW - ilmenite KW - titanite KW - diamond KW - Vinoren KW - Southern Norway Y1 - 2020 U6 - https://doi.org/10.3390/min10111029 SN - 2075-163X VL - 10 IS - 11 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bsdok, Barbara A1 - Altenberger, Uwe A1 - Concha-Perdomo, Ana Elena A1 - Wilke, Franziska Daniela Helena A1 - Gil-Rodriguez, J. G. T1 - The Santa Rosa de Viterbo meteorite, Colombia BT - New work on it's petrological, geochemical and economical characterization JF - Journal of South American earth sciences N2 - Undifferentiated meteorites, like primitive chondrites, can contain presolar and solar nebula materials which would provide information about the origin and initial conditions of the solar system, whereas differentiated meteorites like iron meteorites, can show early phases of planetary accretion. They also provide the possibility to receive information about core properties and planetary bodies. In addition to the gain in such fundamental scientific knowledge both types are of interest for the exploration of critical raw materials (CRMs) and precious elements. The Santa Rosa de Viterbo meteorite shower, discovered 1810 in the Boyaca province of Colombia, represents a typical iron-nickel meteorite. The present study presents new structural, textural and geochemical results of one fragment of this meteorite, using reflecting microscopy, electron probe micro analyses (EPMA) and electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDX). The present study presents trace element concentrations of the meteorite's minerals for the first time. The sample is dominated by kamacite (alpha-FeNi). Schreibersite (FeNi3P), taenite (gamma-FeNi) and plessite (mixture of kamacite and taenite) are minor constituents. The occurrence of cohenite ((Fe,Ni,Co)(3)C) and troilite (FeS) are likely. The meteorite sample contains classical Neuman bands passing through kamacite and frequent Widmanstadtten pattern. The bandwidth of kamacite defines the meteorite as finest octahedrite. Geochemically, it is characterized as a "Type IC meteorite". While improving the characterization and classification of the Santa Rosa de Viterbo Iron Meteorite, notable concentrations of Au (>400 ppm) and Ge (>230 ppm) alongside major elements such as Fe, Ni and Co in the bulk composition of that meteorite, were proven. Major and rock-forming minerals such as kamacite and taenite incorporate hundreds of ppm of Ge whereas schreibersite, itself a minor component in that particular meteorite, is the major source for Au (>1400 ppm). In kamacite and taenite also Ir, Pd and Ga were found in minor amounts. Nano-scale inclusions or atomic clusters called nano-nuggets may have been responsible for the high concentrations of Au, Ir, Pd and Ga. Raman and Laser-induced plasma spectroscopes installed in in space probes seems suitable exploration methods for Fe-Ni meteorites, containing Ni-concentrations > 5.8 wt% defining the meteorite as octaedrites. KW - Fe-Ni-Meteorite KW - Geochemistry KW - Colombia KW - Gold KW - Rare elements KW - Space mining Y1 - 2020 U6 - https://doi.org/10.1016/j.jsames.2020.102779 SN - 0895-9811 VL - 104 PB - Elsevier Science CY - Amsterdam ER -