Caroline L. Smith, Department of Mineralogy, The Natural History Museum, London and Hilary Downes, Birkbeck College, University of London

The Almhata Sitta ureilite shows a number of similarities with previously described anomalous ureilites from the Frontier Mountain region of Antarctica. In this paper we will discuss the similarities (and differences) between these meteorites and review how they fit in with current models of ureilite petrogenesis. We will also discuss how anomalous ureilites like Almahata Sitta may suggest that the ureilite parent body possessed a complex and heterogeneous composition.