Arraias        12°57.29’S, 46°55.03’W

Tocantins, Brazil

Find: 2015 Apr

Classification: Iron meteorite (IIAB)

History: Discovered in April 2015 near the town of Arraias, in the Mata da Ursa region, by a gold prospector named Vicente, in an excavation of gold tailings. He warned his boss about the finding, Mr. Jose Domingos Scarpellini, who subsequently took the meteorite to Curitiba.

Physical characteristics: A mass of 25 kg and approximate dimensions of 12 × 15 × 24 cm, rather smooth, but with large and irregular regmaglypts. There are no signs of fusion crust and it presents a weathered surface showing some with an oxide crust of about 1 mm

Petrography: (Zucolotto, M.E., MN/UFRJ) The etched section shows a typical hexahedrite structure with bright and frosty kamacite areas and several sets of Neumann lines crossing the entire surface. There is no sign of fusion crust and heat affected zone. Troilites are present as small nodules. Phosphides occur as numerous rhabdite crystals as both prisms and plates.

Geochemistry: 5.42% Ni; 0.45% Co; 57.4 ppm Ga; <200ppm Ge; 30.8 ppm Ir; 0.512 ppm Au (INAA, J.T. Wasson, UCLA). Kamacite 5.34% Ni; 0.41% Co. Phosphides 27% Ni; 14.7% P ( EPMA Amanda Tosi LABSONDA/IGEO/UFRJ)

Classification: Iron, IIAB

Specimens: 80g MNRJ, 25 kg Curitiba, Thais Scarpellini