Willcox Playa 009        32°4.6’N, 109°50.73’W

Arizona, United States

Found: 2009 Sept 23

Classification: Mesosiderite

History: A whole stone was recovered by Ruben Garcia while he was hunting for meteorites on Willcox Playa. It was partly buried in the soil.

Physical characteristics: A single ~160 g stone with a smooth weathered surface and deep cracks. It has a reddish-brown weathered surface. Only remnant fusion crust remains.

Petrography: Pyroxene occurs in clasts ranging in size from less than 1 mm to 5 mm surrounded by a network of weathered metal. Silica (to 1 mm) occurs in association with pyroxene. Plagioclase ranges in size from 1 to about 3 mm. Metal (mainly weathered) occurs as an extensive network that surrounds all of the clasts. Troilite (to 1 mm) is heterogeneously distributed. Tetrataenite (to 0.5 mm) is distributed throughout the sample.

Geochemistry: Silicates comprise about 70% of the thin section area; metal and sulfide 30%. The silicate phase is dominated by low-Ca pyroxene (Fs_21-30Wo_0.8-3En_62-78), average plagioclase (An₈₈Ab₁₁Or_0.4) and silica. No olivine was observed. Low-Ca pyroxene is the dominant silicate component, comprising about 64% of the silicate phase and about 45% of the entire thin section; 25% plagioclase; 29% metal; 2% sulfide. Fe/Mn ratio of pyroxene is about 27. Tetrataenite contains 34 - 48 wt% Ni. The kamacite veins are too weathered to be analyzed.

Classification: This meteorite is classified as a mesosiderite. The degree of shock is S1 with a weathering grade of W3.

Specimens: 20 g + TS (LPL); 100 g  + 1 TS + 1 potted butt (ASU).