Paranaíba meteorite, Cancan farm, Cassilândia, Mato Grosso do Sul, Brazili

Regional Level Types
Paranaíba meteorite	Meteorite Fall Location
Cancan farm	Farm
Cassilândia	Municipality
Mato Grosso do Sul	State
Brazil	Country

Ordinary chondrite—black, brecciated, veined (L6,br; S6)
Fall, 1956; 100 kg

A large meteorite, accompanied by detonations, was seen to fall and was evacuated from a 2m deep pit. A large portion of the meteorite was apparently destroyed by local residents. In hand specimens, the meteorite feature's are quite conspicuous as the predominant light round and angular fragments are cut by dark veins and contain broad black areas. A few chondrules are visible in lighter areas, but are absent from darker areas. The lighter areas constitute a monomict breccia, but very fine-grained and variegated opaques occupy the dark veins and dark regions. Total iron contents (Fe 20.86 wt%) along with olivine (Fa23.57) and low Ca-pyroxene (Fs20.7) compositions are characteristic of the L-chondrite geochemical group. Olivine, the predominant phase, is accompanied by lesser amounts of orthopyroxene and albitic plagioclase along with quite minor amounts of troilite and Fe-Ni metal. Accessory chromite, diopside, merrillite and traces of other sulfides and oxides are also reported. The meteorite's dark areas — containing abundant glass and pervasive droplets of Fe-metal and sulfides — are simply the most obvious indicators of very strong pre-terrestrial shocks (level S6). In numerous instances both olivine and orthopyroxene have been converted to weakly isotropic phases or even to completely isotropic glass.

Ar-40-Ar-39 dating of glassy portions of Paranaiba has indicated that the Paranaiba breccia is a mixture of materials which were involved in different (asteroidal) collisions in past eons before they eventually became neighboring constituents of the same earth-bound meteoroid.

The L (relatively low in total iron) chondrites represent ~45% of properly classified meteorite falls with the L6 type by far the largest subset [~70% of L falls]. Of the 271 meteorite falls classified exactly as an 'L6' chondrite Paranaiba is the 9th most massive (as of June 2016). Five L6 meteorites — including 3 falls — have been recovered from Brazil. The 300 kg Putinga fall of 1937 was even more massive.

The largest extant masses (500—1000 g range) have been kept at the Instituto de Geosciências (São Paulo), Museu Nacional-Universidade (Rio de Janeiro), and the United States National Museum (Washington, DC).

Synonyms: Can-Can, Mato Grosso

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