Blanca Estela                     25°00'S, 69°30'W

Chile

Find: 2002

Iron (IAB)

History: A single iron mass of 15.6 kg was discovered by "pirquineros," local miners, in the region of the Guanaco gold mine, NW of Copiapo, northern Chile. The exact find location is withheld. Subsequent to the classification of the first meteorite, two more meteorites of 7 kg and 15 kg have been found in the same area. Their structures and nickel contents indicate that all three meteorites are paired.

Physical characteristics: In the outer parts of the meteorites rust veins follow structure elements.

Petrography: (J. Schlüter, Hamb) The bandwidth of kamacite lamellae is 3 mm. The samples on hand for classification show no inclusions.

Geochemistry: Composition of the metal (INAA): (B. Spettel, MPI) Co = 4.56, Ni = 66.0 (both mg/g), Ga = 93.6, Ge = 380.0, As = 11.4, Ir = 3.97, Au = 1.45 (all µg/g). Noble gases: (L. Franke, MPI) (75.6 mg sample) ³He = 8.55, ⁴He = 36.7, ²⁰Ne = 0.0790, ²¹Ne = 0.065, ²²Ne = 0.0710, ³⁶Ar =0.45, ³⁸Ar = 0.714, ⁴⁰Ar = 5.9 (10^-8 cc STP/g).

Classification: Iron meteorite, (IAB), coarse octahedrite. Noble gas data show that the meteorite is not paired with either Campo del Cielo or Copiapo.

Type specimens: A total of 43.7 g sample is on deposit at Hamb. Gerstenkorn holds the main mass.

Submitted by: J. Schlüter, Hamb.