Sentinel Plain (c)        32°52’26.28"N, 112°57’36.90"W

Arizona, United States

Find: 12 Nov 2018

Classification: Ordinary chondrite (L6)

History: A 540 g meteorite was found by Mr. Robert Szczuczko on 12 November 2018, while he was searching for meteorites in southwestern Arizona.

Physical characteristics: Single 540 g partly fusion crusted blocky stone with shallow to deep regmaglypts. The exterior displays 3 areas of distinct physical characteristics, a thick smooth black-brown thick fusion crust with regmaglypts, a rough surface with shallow black fusion crust and a relatively fresh broken surface revealing the interior. The interior shows some well-defined chondrules separated by a red-stained matrix and scattered metallic grains and occasional metal filled fractures, though no shock vein were discernible.

Petrography: (L. Garvie, ASU, R. Szczuczko) A thin section shows a largely coarsely crystallized meteorite with a smattering of recognizable chondrules. Metal and troilite typically <1 mm in size, though in a few areas the metal is elongated into thin veins. Feldspar commonly >50 μm across. Under crossed polars, the troilite is single crystal and lacks shock features.

Geochemistry: Fa_25.4±0.4, n=24; Fs_21.4±0.3Wo_1.6±0.3, n=18

Classification: L6, S2, W2

Specimens: 36.7 g at ASU