Sample No.: ALHA79045

Location: Allan Hills

Field No.: 1177

Weight (gms): 115.4

Meteorite Type: L3 Chondrite

Physical Description: Roberta Score

A small patch of weathered fusion crust is visible on one surface. What may be remnant fusion crust on two surfaces is iridescent reddish-brown. The remaining three surfaces have weathered to a dull reddish-brown in color but the clastic nature of this meteorite is highly visible. One particular inclusion is 4 mm in diameter and yellow in color. The interior of the stone revealed through chipping is totally weathered. Dimension: 5.5 x 4.5 x 3 cm.

Petrographic Description: Brian Mason

The meteorite consists of a close-packed aggregate of chondrules (0.3-2.1 mm across) and irregular clasts (some of them chondrule fragments), with a relatively small amount of matrix material. Chondrule types include porphyritic and granular olivine and olivine-pyroxene, barred olivine, and fine-grained pyroxene. Some chondrules have black troilite-rich rims. Intergranular glass in chondrules may be transparent and pale brown, but is usually turbid and partly devitrified. Only a small amount of nickel-iron is present. Most of the pyroxene shows polysynthetic twinning. Brown limonitic staining pervades the section. Microprobe analyses show variable composition for both olivine and pyroxene: olivine, Fa2-38, average Fa23; pyroxene Fs2-29, average Fs8. The variability of olivine and pyroxene compositions indicates type 3, and the low metal content suggests L group, so the meteorite is tentatively classified as an L3 chondrite.