Buritizal meteorite, Buritis farm, Buritizal, São Paulo, Brazil

Latitude & Longitude (WGS84):	20° 10' 57'' South , 47° 43' 0'' West
Latitude & Longitude (decimal):	-20.1825, -47.7166666667
Non-native locality type:	Meteorite

Ordinary chondrite, unequilibrated breccia (LL3.2, br; S3; W1).
Fell, 14 August 1967; 210 g.

A locally well documented pre-dawn bolide exploded as night was briefly turned into day. 3 small fragments were kept on a small farm and in 2014 one of the fragments became known to the broader scientific world. Inspections reveal distinct chondrules and chondrule fragments within a gray/black fine-grained, very unequilibrated matrix. All principal types of chondrules (0.8 mm ave. diameter) are present, including esp. porphyritic olivine (PO), porphyritic pyroxene (PP), radial pyroxene (RP) and barred olivine (BO) types. Compositionally, bulk iron contents (20.88 wt%Fe), unequilibrated, quite variable olivine (Fa29.8±13.6) and low Ca-pyroxenes (Fs25.3±16.7) are characteristic of unequilibrated petrologic types of the LL, very low iron, ordinary chondrite geochemical group. Mineralogically the meteorite consists primarily of olivine and low Ca-orthopyroxene and clinopyroxene (including grains of forsterite and enstatite, sensu strictu). Fe-Ni metal grains (2 vol%) are diverse with kamacite (often with tetrataenite inclusions) and lesser amounts of taenite. Moderate pre-terrestrial shock (level S3) and mild weathering are also noted.

Buritizal is a 'genomict breccia' with a number of components originally formed, perhaps, on distinct regions of one or more related asteroidal parent bodies (or nebular proto-asteroids). Its designation as a type 2.3 ordinary chondrite indicates an unusually primitive meteorite which preserves a melange of minerals, textures, and geochemical signatures only mildly altered since they were assembled in the earliest epochs of solar system history. Subsequently brought to earth by collisions and circumstance, Buritizal is one of only 3 witnesses meteorite falls which have been labelled as exactly 'LL3.2' (as of May 2016). The other two are Krymka, the most massive [50 kg], and Vicência, another Brazilian fall. A total of 20 LL3.2 'meteorites', representing at least 9 originally separate meteorites are currently listed. [The 10 Northwest Africa meteorites listed are of unknown provenance and are, most likely, fragments of a much smaller number of actual (unwitnessed) falls.] Thus, Buritizal is truly an unusually rare and valuable meteorite. Hopefully, additional studies of this small meteorite will yield a few more of its secrets.

Mineral List

5 valid minerals.

References

External Links