NWA 2058 an H Pseudotachylite S6 W2
Greg Hupe says it best so I will quote him. "This unique
meteorite cannot be subclassed because of extreme mylonitization.
Mylonitization is fusion of crushed rock under high temperature
by frictional heating. In other words, this meteorite was
formed by a hypervelocity impact on the surface of an asteroid
and cooled within milliseconds as it was ejected out into
space. During the impact event, it was crushed and sheared
simultaneously creating subparallel veins in the direction of
the material flow connecting the elongated metal-sulfide
nodules, talk about odd! Relic grains show evidence of high
strain rates, partially granulated clasts with undulatory
extinction, in contrast to shock features. The matrix consists
mostly of recrystallized olivine. The round objects are not
chondrules but are impact melted and quenched metal sulfide."
