Northwest Africa 10552 (NWA 10552)

(Northwest Africa)

Find: 2000

Classification: Ordinary chondrite (H3-5)

History: 1 stone weighing 314 g was found near Morocco-Algeria border in 2000. Thomas Webb acquired the sample from a meteorite prospector in 2001.

Physical characteristics: The stone is dark brown and has a rounded-irregular shape. The stone is covered by a weathered patina. The cut face of the interior of the stone is dark in color and displays small chondrules, chondrule fragments, and unweathered flakes of metal.

Petrography: Recrystallized and shock-darkened clasts which are set within a host of well-defined, poorly equilibrated chondrules, fragments and clastic debris. Boundaries between clasts and host are obscured by shock-darkened regions within the meteorite. Host chondrules are distinct, have turbid mesostasis, and have an average diameter of 439 μm (n=130). The recrystallized clast is composed of indistinct chondrules and chondrule fragments set within a yellow-stained, recrystallized matrix.

Geochemistry: (A. Love, App) Host: Olivine Fa _18.2±8.6 (Fa_0.9-31.6) N=18; Low Ca pyroxene Fs_16.0±8.0Wo _1.3±0.6 (Fs_3.5-31.5Wo_0.3-2.5), N=12, Equilibrated clasts: Olivine Fa_20.5±0.3, N=4; low-Ca Pyroxene Fs_18.2±0.1Wo_1.9±0.1, N=3.

Classification: Based on textural relationships using optical, CL and SEM microscope images and mineral compositions, this is an H3-5 S3 W3 ordinary chondrite breccia.

Specimens: 2 slices weighing 20.9 g and a polished thin section are on deposit at App.