* Astronomy

Title: Chemical characterization of a "mysterite"-bearing clast from the Supuhee chondrite
Authors: Andrew M. Davis, R. Ganapathy, Lawrence Grossman

HIGucIiI et al. (1977) proposed the existence of Tl-rich and Tl-poor "mysterite" to explain Tl and Bi contents of dark clasts in the Supuhee H6 chondrite and of bulk Supuhee. They suggested that these two components formed by gas-dust fractionation during condensation. An aliquot of one of the clasts studied by Higuchi et al. and found to contain Tl-poor mysterite was analysed by instrumental neutron activation in this paper. A complex assortment of element fractionations was found. Data for rare earth and other refractory lithophiles and refractory and moderately volatile siderophiles are consistent with random separation and reunification of gas and dust throughout the condensation sequence. Independent evidence thus exists that processes like those invoked by Higuchi et al. to explain mysterite did occur in the region of the nebula sampled by this clast.

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