NWA 4502 (4,969 g)
Northwest Africa 4502 (NWA 4502)
Found: Dec 2005
Classification: Carbonaceous chondrite (CV3)
History: Purchased In 2006 by A. Aaronson.
Physical characteristics: More than 100 kg of dark stones with smooth, desert-polished surfaces. The largest piece is 22.75 kg
Petrography: (T. Bunch and J. Wittke, NAU) Well-defined chondrules, chondrule fragments, and refractory inclusions set in a slightly weathered matrix. CAIs are represented by Type A (a few are very large, up to 32 mm in diameter) and Type C are common, as are AOAs. Type B CAIs are low in abundance however, melilite mantled (Type B1) and fosterite bearing type B CAIs are present. Modal analyses (vol. %): chondrules = 48; CAIs and AOAs = 14; matrix = 38.
Geochemistry: (M. S. Sapah, ANU, and A. N. Krot, UHaw) The meteorite matrix consists of small crystals of ferroan olivine, sulfides, magnetite, Ni-rich metal, tiny nepheline crystals, and small irregularly shaped regions of Ca,Fe-rich silicates (pyroxenes ± andradite). Matrix olivine has Fa48-54 and ferrosillite and wollastonite contents of matrix pyroxenes are 11-19% and 46-49% respectively. Fayalite content of chondrule olivine is Fa2-39, and ferrosillite and wollasonite contents of chondrule pyroxenes are 1-2%.
Classification: (M. S. Sapah and A. N. Krot) Carbonaceous chondrite (CV3). The sample is CV oxidized. The degree of shock is S2 and the weathering degree is W1.
Specimens: >83 kg Aaronson, 35 kg Eric Olson, 2.9 kg ANU, 284.6 g ASU, and 26 g NAU.
|Fayalite (mol%):||12.4 (1.6-50.7, N=45)|
|Ferrosilite (mol%):||3.5 (0.7-19.3, N=33)|
|Wollastonite (mol%):||9.3 (0.7-50.9, N=33)|
|Classifier:||M. Sapah, ANU, and A. Krot, UHaw|
|Type spec mass (g):||284.6|
|Type spec location:||ASU|
|Main mass:||Eric Olsen meteorites|
|Comments:||Submitted by Marian S. Sapah|