Cordova        ~33°26’N, ~80°55’W

South Carolina, United States

Find: 1970

Classification: Iron meteorite (IAB-MG)

History: (C.B. Moore, ASU) Two rounded oxidized masses found within 3 km of each other, weighing 7298 and 7250 g, were plowed up around 1970 on two nearby farms owned by Ted Dingley and Harold Brewer near Cordova, South Carolina. They were easily noticed in the fine-grained alluvial soil and relatively heavy compared with other rocks. A third mass was found but its whereabouts is unknown. Other masses were reportedly seen.

Physical characteristics: ASU acquired large masses of each stone. Sections through both masses show them to be dominated by iron oxides and hydroxides with stringers and patches of green Ni-rich secondary minerals ("iron shale" making up about 90% of the meteorite). Both masses contain patches of partially weathered iron and one 26 g "nugget" of unweathered iron. Samples from the nugget were used for the geochemical analysis.

Petrography: (L. Garvie, ASU) The 26 g nugget is dominated by large irregular kamacite grains with swollen outlines, one showing a large array of prominent Neumann bands. The section contains a few mm-sized, regions of comb plessite. The mm-sized schreibersite grains have euhedral to hieroglyphic outlines. A partially weathered 52 g fragments shows a Widmanstätten pattern with swollen kamacite lamellae to 3 mm wide, abundant schreibersite, and a 7 mm troilite nodule.

Geochemistry: Neutron Activation (NA) analysis done at the University of Arizona in 1990 gave Ni 6.5, 6.56 %, Ga 109 and 102 ppm, and Ir 3.9 and 3.76 ppm. These data overlap well with more recent INAA results (J.T. Wasson, UCLA) Ni = 6.89 wt%, Ga = 91.4 ppm, Ge = 476 ppm, As = 9.9 ppm, W = 1.45 ppm, Ir = 3.76 ppm, and Au = 1.423 ppm.

Classification: Iron, IAB-MG. The data overlap closely with Campo del Cielo, but there is no reason to suggest that these meteorites are transported Campos, especially in view of their extreme weathering grade.

Specimens: ASU holds 11.041 kg of which 1220 g contains native metal.