Macroscopic Description: Tim McCoy
The meteorite is a somewhat irregularly shaped mass of ~8 x 4.5 x 4.5 cm. One surface is relatively smooth, with small (1-2 mm) pits and large (1-2 cm), shallow depressions that may be regmaglypts. The opposite surface is highly-irregular in shape, with planar surfaces, larger (~5 mm) deep pits, and linear depressions that can reach a few cm in length and a few mm in width and depth.

Thin Section (,2) Description: Tim McCoy
A longitudinal slice measuring ~3 x 3.5 cm was examined prior to thin section preparation. The slice exhibits a prominent reheated α2 structure around the entire margin, reaching to a depth of up to 5 mm. The section includes inclusions of rounded to elongate troilite (up to 2 x 10 mm), sometimes occurring with silicates, as well as silicate-dominated inclusions, the largest of which reaches 7 mm in diameter and is truncated by the surface. Inclusions are rimmed by swathing kamacite, set inside a Widmanstätten pattern indicative of formation from a single austenite crystal and with kamacite bandwidths of ~1 mm. Examination of the polished thin section reveals that the polyminerallic inclusions consist of orthopyroxene (Fs₁₉Wo₁), augite (Fs_8-11Wo_32-42), potassium feldspar (An_0-3Or_25-58), phosphate (probably whitlockite), chromite and troilite. The inclusion mineralogy does not exactly match other known meteorites, but is similar to IIE irons such as Miles. No fusion crust is present and a weathered zone ~100 µm thick overlies a reheated zone reaching to 0.5 mm depth. The meteorite is dominated by short, wide (~0.8 mm) kamacite lamellae with rectangular and triangular plessite fields. A microprobe traverse yields an average composition of 8.3 wt.% Ni, 0.04 wt.% P and 0.54 wt.% Co. The Ni concentration is similar to other IIE irons (e.g., Kodaikanal). The meteorite is an iron, probably from group IIE.

Thin Section Images

Reflected Light TYR 05181

Lab Images