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. It may be a derivative of the former and a precursor of the latter.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. Hexamolybdenum is part of a continuum of high-temperature alloys in meteorites supplying a link between Os- and/or Ru-rich and Fe-rich meteoritic alloys. Allendeite may have been an important ultrarefractory carrier phase linking Zr-,Sc-oxides to the more common Sc-,Zr-enriched pyroxenes in Ca-Al-rich inclusions. The two minerals reflect conditions during early stages of the formation of the Solar System. The name hexamolybdenum refers to the symmetry (primitive hexagonal) and composition (Mo-rich). Allendeite is named after the Allende meteorite. Hexamolybdenum is hexagonal, P6 3/ mmc, a = 2.7506, c = 4.4318 Å, V = 29.04 Å 3, and Z = 2, with a calculated density of 11.90 g/cm 3 via the known structure and our observed chemistry.
Allendeite is trigonal, R3̄, a = 9.396, c = 8.720, V = 666.7 Å 3, and Z = 3, with a calculated density of 4.84 g/cm 3 via the previously described structure and our observed chemistry. They are allendeite, Sc 4Zr 3O 12, a new Sc- and Zr-rich oxide and hexamolybdenum (Mo,Ru,Fe,Ir,Os), a Mo-dominant alloy. During a nanomineralogy investigation of the Allende meteorite with analytical scanning electron microscopy, two new minerals were discovered both occur as micro- to nano-crystals in an ultrarefractory inclusion, ACM-1.
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