Yucca 051        34°48.990’N, 114°16.151’W

Arizona, United States

Find: 11 Nov 2011

Classification: Ordinary chondrite (H6)

History: Found 5 cm below the surface by Jim Wooddell on November 11, 2011 while searching with a metal detector. Mr. Wooddell donated the main mass to Cascadia.

Physical characteristics: Sample is almost entirely covered with weathered fusion crust. A rusted light-colored interior is visible in two small patches where crust is missing.

Petrography: In thin section, the sample appears to be well integrated and relatively coarse-grained, containing chondrules with boundaries that blend into their surroundings. Crystalline plagioclase feldspar grains are typically 30-40 µm across, although a few grains > 100 µm across were observed. Metallic copper and several chromite-plagioclase objects are present.

Geochemistry: (M. Hutson and A. Ruzicka, Cascadia) The major silicate phases are equilibrated, including olivine (Fa_19.9±0.5, N=20), low-Ca pyroxene (Fs_17.3±0.5Wo_1.4±0.4, N= 16), diopside (Fs_6.4±2.0Wo_46.4±1.4, N= 5), and plagioclase feldspar (Ab_77.7±1.7An_15.1±1.4Or_7.2±1.1, N=8)

Classification: Mineral chemistry indicates an equilibrated H chondrite. A petrographic grade of 6 (near the 5/6 border) is suggested by the sample?s well-integrated texture and the sizes of the plagioclase feldspar grains.

Specimens: Cascadia holds 21.7 g in one piece, in addition to a polished thin section. Jim Wooddell holds a 3.8 g end cut and a polished thin section.