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。 - 17.7 g - (1)

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

Classification: HED 变质包裹陨石（Diogenite, 异常）

History: 报道称，一组陨石猎人于2022年12月27日在阿尔及利亚 Djebel Chaab DCA 地区发现了该物质的若干碎片。

Petrography (K. Metzler, IfP): 多岩相“变晶质”角砾岩，由矿物碎片及少量岩质碎片（地榴辉石族Diogenite与辉石族Eucrite）嵌入细粒相关碎屑中。材料经历冲击压实，存在薄的冲击脉。Diogenite 成分占比>90体积%。该角砾岩以橄榄石和低 Ca 辉石碎片为主，化学成分范围异常宽广。Eucrite 成分以矿物碎片（析出辉石、斜方辉石、SiO2 同晶多形体）和小岩质碎片的形态存在。配石包括 Cr-尖晶石和含 Ni 金属（Ni 含量3-4 wt%）。

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: high
Weathering grade: low
Classifier: K. Metzler, IfP

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