Nova 057

Baja, Mexico

Find: 1984

Classification: Iron meteorite (IIAB)

History: Purportedly found in Baja California, Mexico, in 1984

Physical characteristics: The 26.5 kg meteorite is oblong, with a red-brown exterior, regmaglypts of varying size, and measures approximately 40 cm × 18 cm × 15 cm.

Petrography: (C. Herd, UAb) Optical investigation of a small (~1.5 × 2.0 cm) polished and etched slice reveals a Widmanstaetten pattern consistent with a coarsest octahedrite (6-7 mm). No obvious inclusions were noted. Terrestrial alteration appears to have only affected the exterior surface.

Geochemistry: ICP-MS data, using sample of North Chile (Filomena) as standard (C. Herd and G. Chen UAb): Ni = 5.9, Co = 0.47 (both wt%); Ir = 9.6, Ga = 48, As = 6.4, W = 2.4, Re = 0.8, Os = 1.0, Pt = 17.9, Cu = 101, Au = 0.9 (all µg/g).

Classification: IIAB iron, through comparison of bulk composition with data from Wasson et al. (2007), coarsest octahedrite. Composition is distinct from other known IIAB irons from Mexico, and this is the first known IIAB iron from Baja California.

Specimens: Type specimen consisting of 23 g in four slices at UAb. Main mass with the anonymous owner.