Sample No..: ALH84188, 84206, 84250, 84254

Location: Allan Hills

Field Nos.: 2837; 2686; 2813; 1544

Weight (g): 3.1; 15.1; 10.0; 2.0

Dimensions (cm): 1x2x0.7; 2x2x1; 2x2x1; 1.5x1.5x0.4

Meteorite Type: E4 Chondrite

Macroscopic Description: Roberta Score,

All four specimens retain some fusion crust (84254 is totally covered with fusion crust). The interiors of 84206 and 84250 are black with inclusions as large as 2 mm in diameter, while the interiors of 84188 and 84254 are black and have a massive texture. Metal is present in 84206 and 84254. 84188 is extensively weathered; the others are minimally to moderately weathered.

Thin Section (ALH84188,2) Description: Brian Mason

Chondrules are relatively abundant, but are small, usually about 0.6 mm in diameter; they consist of fine-grained to coarsely granular pyroxene. The matrix consists largely of chondrule fragments and pyroxene grains, with a moderate amount of nickel-iron and sulfides. The meteorite is considerably weathered, with brown limonitic staining throughout the section. Micro-probe analyses show that most of the pyroxene is almost pure MgSiO3, but a few grains show FeO up to 2.7%. The nickel-iron contains 2.5% Si. The meteorite is an enstatite chondrite, and since some of the pyroxene is polysynthetically twinned clinoenstatite, it is classed E4. It closely resembles ALH81189, 82132, 84206, 84250, and 84254, and the possibility of pairing should be considered.