Sample No.: ALHA77271

Location: Allan Hills

Field No.: Y78010603

Weight (gms): 609.5

Meteorite Type: H6 Chondrite

Physical Description:

This is a complete, rounded specimen. Approximately 25% of the total sample is covered with a dull black fusion crust. The crust appears in small patches on the meteorite's surface and is approximately 1 mm thick. The portion of the meteorite not covered with fusion crust is a dark brown weathered surface. Small inclusions are visible on this surface. The sample was difficult to chip. When the material was collected for thin section preparation, no fresh metal was observed. The sample fractured along a small fissure. The interior of the bulk meteorite was weathered along this fissure. Dimensions approximately 8.0x7.5x5.0 cm.

Petrographic Description: Brian Mason

Chondrules are sparse and tend to merge with the granular groundmass, which consists largely of subequal amounts of olivine and orthopyroxene with minor amounts of nickel-iron (~20%), plagioclase (~10%), and troilite (~5%). Microprobe analyses show olivine (Fa19), orthopyroxene (Fs16), and plagioclase (An13) of uniform composition. The section shows a moderate degree of weathering, with small areas and veins of brown limonite.