A 1.0 x 1.5 cm slice of this meteorite was examined. This section consists of equidimensional kamacite grains up to 2.5 mm wide with interstitial ribbons of taenite and schreibersite. At the edges of the meteorite, kamacite exhibits the α2 structure. Within and crosscutting kamacite grains are swarms (up to 1 mm in size) of equant graphite crystals up to 50 microns in maximum dimension (in one case, associated with sulfide). The shape of the graphite crystals is largely controlled by the structure of the metal. Elongate areas reaching 4 mm in length are also composed of swarms of elongate graphite. The average composition based on a microprobe traverse of 100 points is 8.9 wt% Ni, 0.9 wt% P. The meteorite is anomalous but may be related to graphite-rich IAB irons, e.g. Kendall County. |