Little Harquahala Mountains        33°41.506’N, 113°38.167’W

Arizona, La Paz County, USA

Found: Jan 2006

Classification: Ordinary chondrite (H, melt rock)

History: Russell Williams found a single stone in 14 pieces while prospecting for gold in the Little Harquahala Mountains of Arizona, La Paz County, on January 2006.

Petrography: (Laurence Garvie, ASU) Low-Ca pyroxene and olivine with lesser albitic plagioclase, Fe-Ni, troilite and minor Ca-phosphate, Cr-rich diopside, and Al-rich glass. Much of the metal has been oxidized. The rock is mostly recrystallized and fine-grained, without recognizable chondrules. The grains display a hypidiomorphic texture. The section is dominated by subhedral and polygonal low-Ca pyroxene (typically 0.1 to 0.3 mm, some to 0.7 mm) and euhedral to anhedral olivine (typically <50 μm, with sparse grains to 0.2 mm). The pyroxene occurs as clusters showing a granoblastic texture, with intervening finer-grained pyroxene, olivine, and intersertal plagioclase. The low-Ca pyroxene grains contain an abundance of chadacrysts and inclusions, primarily olivine, but also Cr-rich diopside, Al-rich glass, and troilite.

Geochemistry: (Laurence Garvie, ASU) Olivine Fa_19.25 (range 18.43 to 19.68), with FeO/MnO = 38.49; low-Ca pyroxene Fs_16.92Wo_4.38 (Fs ranges from 16.10 to 18.66 and Wo from 3.19 to 7.12); and plagioclase An_16.43Or_2.36. One 50-μm diopside grain was found Fs_9.28Wo_39.22 with 1.2 wt% Cr₂O₃. Oxygen isotopes replicate analyses (R. Tanaka, OkaU) of acid washed, bulk sample by laser fluorination gave δ¹⁷O = 3.147 and 3.158‰; δ¹⁸O = 4.571 and 4.750‰; Δ¹⁷O = 0.739 and 0.656‰.

Classification: H chondrite melt rock, degree of weathering is moderate and shock is low. The meteorite lacks a chondritic texture but has mineral and oxygen isotope compositions with H-chondrite affinities. This stone shows similarities with NWA 2353, 2635, and 3145.

Specimens: ASU holds 25.98 g and three thin sections. Main mass R. Williams and J. Blennert.