Sample No.: CMS 04049 Location: Cumulus Hills Field No.: 14086 Dimensions (cm):   6.0x2.5x3.5 Weight (g): 90.209 Meteorite Type: Eucrite (Unbrecciated)

Macroscopic Description: Kathleen McBride
40% of the exterior is covered with black fusion crust with shiny patches. The interior consists of black and white mineral grains with some gray globs and translucent, tabular shaped minerals.

Thin Section (,4) Description: Tim McCoy
The section shows an unbrecciated intergrowth of coarse (up to 1 mm) pyroxene and plagioclase grains with a gabbroic texture. Pyroxene is exsolved to orthopyroxene (Fs₅₀Wo₅) and augite (Fs₂₈Wo₄₁) (Fe/Mn ~30) and plagioclase is An_79-91Or_0-1. Shock effects are extensive including darkening of silicates. The meteorite is an unbrecciated eucrite.

CMS 04049 Partially Cross-Polarized Light	CMS 04049 Reflected Light	CMS 04049 Partially Cross-Polarized Light

Sample No.: CMS 04061-04079 Location: Cumulus Hills Field No.: 14682; 14627; 14639; 14614; 14076; 14611; 14608; 14688; 14698; 14660; 14669; 14693; 14663; 14604; 14647; 14609; 14619; 14606; 14664 Dimensions (cm):   23.0x17.0x10.0; 18.0x17.5x21.0; 19.0x12.0x16.0; 37.5x19.5x15.0; 15.0x13.5x12.5; 16.5x11.5x9.5; 10.5x20.0x14.0; 41.0x24.0x13.0; 40.0x36.0x19.5; 16.0x9.0x10.0; 13.0x9.0x8.0; 15.5x7.5x9.5; 12.0x8.0x10.0; 10.0x4.5x5.0; 2.0x2.0x1.0; 2.5x1.5x1.5; 20.0x15.5x10.0; 17.5x14.5x9.5; 19.5x14.5x15.0 Weight (g): 8465.0; 15315.0; 6188.3; 19195.0; 5738.0; 5877.0; 7561.9; 20425.0; 44700.0; 3515.8; 2110.1; 2312.9; 928.2; 325.7; 9.592; 8.252; 9625.0; 5695.2; 12550.0 Meteorite Type: Pallasite

Macroscopic Description: Tim McCoy and Linda Welzenbach
These meteorites are pallasites with common exterior morphology and weathering. They range in mass from 8.2 g to 44.7 kg. They all exhibit a very weathered, rusty exterior with extensive removal of olivine, leaving voids that range in size from a few millimeters to many centimeters. The larger cavities probably resulted from extensive olivine removal during physical and chemical weathering and weathering of any residual metallic matrix.

Thin Section (,4) Description: Tim McCoy

Reflected Light

CMS 04071 was selected for examination. This mass is typical of the group in exterior morphology and weathering and of moderate size (2.11 kg). Two slices were cut from the center of the mass, each measuring ~9 cm by 6 cm. These slices exhibit fragmental, angular olivine grains ranging in size from a hundred microns to 2 cm in size. Olivine grains exhibit extensive iron oxide staining, producing olivine grains that range from brown near the margins of the slice to green in the interior. Interstitial to these grains are euhedral and irregular chromites, as well as troilite and schreibersite. Olivine is Fa₁₂ and the texture, mineralogy and even degree of weathering are reminiscent of Imilac. The meteorites are pallasites, probably members of the main group.

Sample No.: LAR 04315 Location: Larkman Nunatak Field No.: 15558 Dimensions (cm):   12.5x7.0x5.0 Weight (g): 1164.8 Meteorite Type: Ureilite (Anomalous)

Macroscopic Description: Kathleen McBride
Dark brown/black patchy fusion crust covers 65% of the exterior. Exposed interior is dark in color with lighter inclusions. The interior is dark, ultramafic with a few light inclusions. This hard meteorite is rusty and has a coarse grained texture. Weathering is more extensive near the exterior.

Thin Section (,7) Description: Tim McCoy
The section consists of an aggregate of large olivine and pyroxene grains up to 2 mm across. Olivine grains are rimmed by carbon-rich material containing traces of metal. While these metal-bearing rims appear to define individual olivine crystals, those crystals exhibit subdomains a few hundred microns across in transmitted light and no reduction is observed between the subdomains. Olivine has cores of Fa₁₉, with rims reduced to Fa₂. Metal and sulfide form veins between the olivines, with metal often forming rounded blebs within the sulfide. The pyroxene grains are dominantly pigeonite (Fs_7-9Wo_7-9) and exhibit a wormy texture with elongate and irregular voids (graphite-filled?), and inclusions of metal and sulfide (sometimes associated with the voids). Within the pigeonites, but distinct from the voids, are found inclusions of subcalcic augite (Fs_7-9Wo_24-28) and, in association, an apparently non-stoichiometric phase highly enriched in SiO₂, and contains Al₂O₃. The meteorite is an anomalous ureilite.
Oxygen isotope analysis - J. Farquhar:
δ¹⁸O = 7.2 per mil; Δ¹⁷O = -0.8 per mil

LAR 04315 Cross-Polarized Light	LAR 04315 Reflected Light	LAR 04315 Cross-Polarized Light	LAR 04315 Reflected Light	LAR 04315 Cross-Polarized Light

Sample No.: LAR 04316 Location: Larkman Nunatak Field No.: 15577 Dimensions (cm):   12.0x7.0x7.0 Weight (g): 1163.0 Meteorite Type: Aubrite

Macroscopic Description: Kathleen McBride
Very little fusion crust is left on the exterior surface. The three areas of remaining crust are brown/black in color and have the characteristic "bubbly" appearance. There are some areas of yellow crusty material. The interior has a light gray matrix with large, angular white and gray clasts. Smaller clasts are usually white. There is a large 2.5 cm black clast with rust located in the center of the break. The interior contains multiple dark gray to almost black angular clasts with basaltic texture.

Thin Section (,3 ,4 ,7) Description: Tim McCoy
Section ,3 samples a comminuted matrix of essentially FeO-free enstatite (Fs_0-1) and diopside (Fs₁Wo₄₅) with grain sizes reaching 3 mm and rarer metal, phosphide, troilite, daubreelite and alabandite. This material makes up the bulk of the meteorite. Two clasts described in the macroscopic description, and apparently in contact in the piece, are an aubrite basalt vitrophyre of the type recently described by Fogel (GCA 69, 1633-1648) composed of enstatite (Fs₂) and forsterite (Fa₂) in a matrix of feldspathic glass and a metal-sulfide quench-textured clast with a single 0.5 mm alabandite grain. The meteorite is an aubrite.

LAR 04316 Cross-Polarized Light	LAR 04316 Reflected Light	LAR 04316 Cross-Polarized Light
LAR 04316 Reflected Light	LAR 04316 Reflected Light	LAR 04316 Reflected Light

Sample No.: LAR 04317; LAR 04318 Location: Larkman Nunatak Field No.: 15551; 15495 Dimensions (cm):   2.0x2.0x1.0 4.5x2.5x3.0 Weight (g): 10.360; 53.304 Meteorite Type: CK4 Chondrite

Macroscopic Description: Kathleen McBride
~90% of the exterior surface is covered with thick brown/black fusion crust with polygonal fractures. The interiors are composed of gray matrix with large chondrules and are very hard.

Thin Section (,3 ,4) Description: Tim McCoy
These meteorites are so similar that a single description suffices. The sections consist of large (up to 2 mm) chondrules and isolated mineral grains in a matrix of finer-grained silicates, sulfides and very abundant magnetite. Olivine is Fa_29-32 and calcic pyroxene is Fs₁₀Wo₄₅. The meteorites are CK4 chondrites.

LAR 04317 Cross-Polarized Light	LAR 04317 Reflected Light	LAR 04317 Cross-Polarized Light	LAR 04317 Reflected Light

Macroscopic Description: Kathleen McBride
The exterior of this carbonaceous chondrite is covered with 100% thick brown/black fusion crust with polygonal fractures. The interior is a black matrix with tiny white inclusions.

Thin Section (,3) Description: Tim McCoy

Cross-Polarized Light	Reflected Light

The section consists of numerous small chondrules (up to 1 mm), mineral grains and CAIs set in a black matrix; rare metal and sulfide grains are present. Chondrules exhibit relatively little alteration and are set in a matrix of serpentine. Olivine compositions are Fa_0-27, with a strong peak at Fa_0-2. The meteorite is a CM2 chondrite.