陨石。Diogenite - 异常的，（Djebel Chaab 004） 罕见且难以获得。这是仅有的13块被批准归类为 Diogenite-an 的陨石之一。 - 5 g - (1)

Djebel Chaab 004 (Cha 004) 25.33805°N, 1.14363°E
Adrar, Algeria
Find: 2022 Dec 27

Classification: HED achondrite (Diogenite, anomalous)

History: 据称，一组陨石猎人在2022年12月27日于阿尔及利亚的Djebel Chaab DCA发现了若干该物质的碎块。

Petrography (K. Metzler, IfP): 多晶质无球粒陨斗碎碎屑角岩，包含矿物片段与少量岩质碎屑（斜长岩型与橄榄石型斜方岩）嵌在细粒相关碎屑中。材料经历冲击致密化，存在薄层状冲击脉。Diogenite组分>90体积%。该碎岩以橄榄石与低-Ca辉石的碎片为主，化学成分范围异常广。Eucrite组分以矿物片段（共生斜辉石、斜 long 斜长石、SiO2多形态）和小岩质碎片的形式出现。附件包括Cr-spinel与含Ni金属（3-4 wt% Ni）。

Geochemistry: Mineral compositions and geochemistry: Diogenitic clasts: Mean olivine composition: Fa15.9±5.8 (Fa8.7-28.4); Fe/Mn (at.): 44.8; n=18. Mean pyroxene composition: Fs23.5±5.9Wo2.3±1.1 (Fs11.9-31.2Wo0.4-3.9); Fe/Mn (at.): 28; n=15. Eucrite clasts: Mean composition of low-Ca pyroxene (host): Fs63.3±0.3Wo2.4±0.4 (Fs62.8-63.7Wo1.9-2.8); Fe/Mn (at.): 33; n=5. Mean composition of Ca-rich pyroxene (exsolution lamellae): Fs25.7±4.5Wo40.7±1.8 (Fs21.2-31.5Wo36.6-42.2); Fe/Mn (at.): 33; n=11. Mean plagioclase composition: An89.6±5.1Or0.4±0.5 (An78.3-95.1Or0.0-1.5); n=15.

Classification: Diogenite (polymict, anomalous). The diogenite component is characterized by unusually large chemical variations of both olivine and pyroxene, which distinguishes this rock from other polymict diogenites.

Shock stage: 高
Weathering grade: 低
Classifier: K. Metzler, IfP

This lot comes with certificate of authenticity.
Thanks for your interest.