Lodranites
This group of primitive achondrites is named for the type
specimen, Lodran, a meteorite that fell in Pakistan in 1868. There
are only 11 members in this group, and nearly all of them have been
found in the blue-ice fields of Antarctica. It is somewhat of a
mystery why no new lodranite specimens have been discovered thus far
as part of the wealth of new meteorites coming from the hot deserts
of Africa and Asia.
Initially, the lodranites were grouped with the stony-iron
meteorites since they contain components of both stony material,
consisting of olivine, orthopyroxene, and minor plagioclase, and
nickel-iron metal in nearly equal proportions. However, since the
discovery of the closely related acapulcoite group, the lodranites
have been classified as primitive achondrites. Because both groups
share similar mineralogical and oxygen isotopic compositions, it is
thought that they are derived from the same parent body, most likely
an S-type asteroid that has not yet been identified. Lodranites have
coarser-grained olivines and pyroxenes and experienced higher
temperatures than acapulcoites; these facts indicate that the
lodranites have their origin within the deeper layers of the
acapulcoite/lodranite parent body where they were subjected to a
more intense and prolonged thermal processing.
Outside Lodran, it's the first
lodranite to be available for the collectors
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