Sample No.: RKPA80239

Location: Reckling Peak

Field No.: 1098

Weight (gms): 5.6

Meteorite Type: Ureilite

Physical Description: Roberta Score

Thin patchy fusion crust appears on all surfaces of this achondrite. Areas devoid of fusion crust are crystalline, reddish-brown in color and rough in texture. The interior is black to reddish-brown in color and crystalline (?). Sample has weathered differently than other samples in the Antarctic collection. Dimensions: 2 x 1.5 x 0.5 cm

Petrographic Description: Brian Mason

The section shows an aggregate of anhedral grains (0.3-1.5 mm across) of olivine with minor amounts of pyroxene. The grains are rimmed with black carbonaceous material. Trace amounts of troilite and nickel-iron are present, the latter largely altered to translucent brown limonite concentrated along grain boundaries. Microprobe analyses show olivine of uniform composition (Fa16) with notably high CaO content (0.3-0.4%); the pyroxene is a pigeonite of composition Wo5Fs15En81. This meteorite is a ureilite; it appears to be relatively lightly shocked compared to most ureilites.