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| Registry: | AB521 |
| Mineral Name: | Patos de Minas |
| Source: | Brazil |
| Mineral Size: | 524.0g |
| Sale Price: | $4,200.00 |
Description: |
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A large, very weathered, mass of about 200 kilos was found on a Brazilian hacienda in 2002.
John Wasson of UCLA, published this in the Meteoritical Bulletin #93:
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Patos de Minas (octahedrite) 18°35'S, 46°32'W
Patos de Minas, Minas Gerais state, Brazil
Find: 1925; main mass in 2002
Iron (IAB complex)
History: A small (18.4 g) end piece of a badly oxidized octahedrite was found in 1925 at the collection of the Escola de Minas Ouro Preto. In 1960 it was donated to Museu Nacional of Rio de Janeiro. The meteorite was mentioned in the British Museum catalog and the Handbook of iron meteorites of Buchwald, when it was named Patos de Minas (octahedrite), or Patos II, to distinguish it from Corrego do Areado, or Patos de Minas (hexahedrite). In 2002, a mass of about 200 kg was found by Paulo Garcia when plowing the land with a tractor.
Physical characteristics: One
mass of about 200 kg has average dimensions of 54 × 33 × 22 cm. It is rough, elongated
and very weathered, exhibiting some grooves due to terrestrial corrosion and with no signs
of fusion crust.
Description: Polished sections display a poor medium Widmanstätten structure of
irregular kamacite lamellae 1.1 ± 0.2 mm (max. 2.4 mm), with the Widmanstätten pattern
not very obvious. Aspect ratios (length/width) of individual lamellae range from 1 to 8,
most being 4-6. Terrestrial corrosion penetrates to a depth of 5 cm. Troilite nodules are
very common. The structure is identical to Patos de Minas (octahedrite) so the two masses
are considered to be paired.
Geochemistry: (John T. Wasson, UCLA, data obtained by INAA). Bulk composition: Co = 4.8, Ni = 83 (both mg/g); Ga = 67, Cu = 240, As = 15.4, Ir = 1.3 and Au = 1.7 (all in µg/g).
Classification: Iron (IAB complex); very weathered
Type specimens: A total of 1200 g of sample is on deposit at Museu Nacional/UFRJ/Rio de Janeiro, Brazil. The main mass was recently sold by the finder.
Part slice, about 128 x 81 x 9mm.
All the Patos de Minas specimens currently available here were professionally prepared in early December 2007, and are stable.