Geochimica et Cosmochimica Acta, 51, 3155–3173. (1987) Zelda and company: Petrogenesis of sulfide-rich Fremdlinge and constraints on solar nebula processes. Search in Google ScholarĪrmstrong, J.T., Hutcheon, I.D., and Wasserburg, G.J. (1985b) Ni-Pt-Ge-rich Fremdlinge: Indicators of a turbulent early solar nebula. Geochimica et Cosmochimica Acta, 49, 1001–1022. (1985a) Willy: A prize noble Ur-Fremdling–-Its history and implications for the formation of Fremdlinge and CAI. 10.1029/98JB00576 Search in Google ScholarĪrmstrong, J.T., El Goresy, A., and Wasserburg, G.J. Journal of Geophysical Research, 103, 9917–9929. (1998) Sulfur in serpentinized oceanic peridotites: Serpentinization processes and microbial sulfate reduction. References citedĪlt, J.C., and Shanks, W.C. We thank Klaus Keil, Mike Zolensky, and associate editor Steven Simon for helpful reviews. SEM, EBSD, and EPMA analyses were carried out at the Caltech GPS Division Analytical Facility, which is supported, in part, by NSF Grants EAR-0318518 and DMR-0080065. It is likely that the fluid became relatively more Sn- and Te-enriched with time and that crack fillings post-date vein fillings, possibly due to a late remobilization of vein sulfides. As only sections in one half of ACM-2 contain nuwaite/butianite, they were probably derived through a relatively low f O2- f S2 sulfidation process, in which a highly localized, low-temperature Ge-, Sn-bearing fluid interacted with a portion of the host CAI. These phases and associated heazlewoodite and Ge-bearing alloys are observed only within the Ca-,Al-rich inclusion (CAI) and not outside it or at the inclusion-matrix interface. Nuwaite and butianite are very late-stage, vapor-deposited, alteration products, filling in pores within preexisting grossular-rich alteration veins and cracks in igneous Al,Ti-diopside. Nuwaite and butianite are the first known meteoritic minerals with high Ge and Sn concentrations. Their calculated densities are 7.24 and 7.62 g/cm 3, respectively. Both nuwaite and butianite have an I4/ mmm inter-growth structure with a = 3.65 Å, c = 18.14 Å, V = 241.7 Å 3, and Z = 2. Butianite’s simplified formula is Ni 6(Sn,Ge) (S,Te) 2 and the end-member formula is Ni 6SnS 2. The simplified formula is Ni 6(Ge,Sn)(S,Te) 2, leading to an end-member of Ni 6GeS 2. Nuwaite (Ni 6GeS 2, I MA 2013-018) and butianite (Ni 6SnS 2, I MA 2016-028) are two new chalcogenide minerals, occurring as micrometer-sized crystals with grossular, Na-bearing melilite, heazlewoodite, and Ge-bearing Ni-Fe alloys in veins and as mono-mineralic crack-filling material in igneous diopside in the Type B1 Ca-Al-rich inclusion (CAI) ACM-2 from the Allende CV3 carbonaceous chondrite.
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