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Abstract?The angrites are a small and heterogeneous group of achondritic meteorites with highly unusualchemical and mineralogical features. The abundant presence of glasses in D?Orbigny makes this rock a uniquemember of the angrite group. Glasses fill open spaces, form pockets, and occur as inclusions in olivines. Theirphysical settings exclude an incorporation from an external source. Major and trace element (rare earthelements [REE], Li, B, Be, transition elements, N and C) contents of these glasses and host olivines weremeasured combining laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), secondaryionmass spectrometry (SIMS), Nuclear Reaction Analysis (NRA), and EMP techniques. Based on the majorelement composition, glasses filling voids could represent either a melt formed by melting an angritic rock ora melt from which angrites could have crystallized. Trace element contents of these glasses strongly indicatea direct link to the D?Orbigny bulk meteorite. They are incompatible with the formation of the glasses bypartial melting of a chondritic source rock or by shock melting. The refractory elements (e.g., Al, Ti, Ca) haveabout 10 CI abundances with CaO/TiO2 and FeO/MnO ratios being approximately chondritic. Traceelement abundances in the glasses appear to be governed by volatility and suggest that the refractory elementsin the source had chondritic relative abundances. Although the glasses (and the whole rock) lack volatileelements such as Na and K, they are rich in some moderately volatile elements such as B, V, Mn, Fe (all withclose to CI abundances), and Li (about 3?5 CI). These elements likely were added to the glass in asub-solidus metasomatic elemental exchange event. We have identified a novel mechanism for alteration ofglass and rock compositions based on an exchange of Al and Sc for Fe and other moderately volatile elementsin addition to the well-known metasomatic exchange reactions (e.g., Ca-Na and Mg-Fe).Because glass inclusions in olivine were partly shielded from the metasomatic events by the host crystal,their chemical composition is believed to be closer to the original composition than that of any other glasses.The relative trace element abundances in glasses of glass inclusions in olivine and glass pockets are alsounfractionated and at the 10 to 20 CI level. These glasses are chemically similar to the common void-fillingglasses but show a much wider compositional variation. Inclusion glasses demonstrate that at least olivinegrew with the help of a liquid. In analogy to olivines in carbonaceous chondrites, initial formation could alsohave been a vapor-liquid-solid condensation process. At that time, the glass had a purely refractorycomposition. This composition, however, was severely altered by the metasomatic addition of large amountsof FeO and other moderately volatile elements. The presence of volatile elements such as carbon and nitrogenin glasses of glass inclusions is another feature that appears to give these glasses a link with those hosted byolivines of carbonaceous chondrites. All these features point to an origin from a vapor with relativeabundances of condensable elements similar to those in the solar nebula. Copyright © 2003 Elsevier Ltd

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