The CV (Vigarano-type) chondrites are a petrologically diverse group of meteorites that are divided into the reduced and the Ball-like and Allende-like oxidized subgroups largely based on secondary mineralogy (Weisberg et al., 1997; Krot et al., 1998b). Some chondrules and calcium-aluminum-rich inclusions (CAIs) in the reduced CV chondrite Vigarano show alteration features similar to those in Allende: metal is oxidized to magnetite; low-Ca pyroxene, forsterite,;and magnetite are rimmed and veined by ferrous olivine (Fs(40-50)); and plagioclase mesostases and melilite are replaced by nepheline and sodalite (Sylvester et al., 1993; Kimura and Ikeda, 1996, 1997, 1998).