润棠旭棠 发表于 2020-3-13 18:01:14

Angrite钛辉无球粒陨石-Dorbigny

D'Orbigny名字,是最大的一块angrite陨石,16.55kg。
钛辉无球粒陨石,是极其稀少的无球粒陨石,当前的价值甚至不低于月球和火星。
密度一般大于3.2,内部还存有2.3厘米直径的晶洞,还有少量的厘米大小的橄榄石晶体颗粒。

D'OrbignyBuenos Aires, ArgentinaFound 1979 JulyAngriteA 16.55 kg stone, mostly covered with dark gray fusion crust, was found in a corn field after a farmer hit it with a plow.Classification and mineralogy (F. Brandstätter and G. Kurat, NHMV): has a sub-ophitic texture, exhibiting laths of plagioclase (An>99, up to 2 mm) with subhedral to euhedral augite and anhedral to subhedral olivine; augite shows marked optical zoning, with cores containing 1.6 wt% TiO2, 7.8 wt% Al2O3, XMg = 26.8 mol%, XFe = 21.9 mol%, and XCa = 51.2 mol%, and reddish-brown rims with 4.0 wt% TiO2, 8.0 wt% Al2O3, XMg = 0.6 mol%, XFe = 46.7 mol%, and XCa = 52.6 mol%; olivine is zoned, with cores having Fa39.7La1.3 (La = larnite), 0.9 wt% CaO, 0.13 wt% Cr2O3, 0.45 wt% MnO, and rims having Fa75.9La11.5, 6.6 wt% CaO, 0.12 wt% Cr2O3, 0.93 wt% MnO; in places, anhedral kirschsteinite (Fa62.0La34.0, 20.0 wt% CaO, 0.11 wt% Cr2O3, 0.75 wt% MnO) is intergrown with olivine; in places, abundant ultrabasic glass fills pore spaces (SiO2 ≈40 wt%); minor to accessory phases include transparent brownish spinel (up to 500 μm), ulvöspinel, troilite, and a silicophosphate; contains abundant round vugs, up to 2.3 cm in diameter, and druses containing augite and rare centimeter-sized green olivine crystals (Fa9–11); rock is fresh, but pores contain variable amounts of caliche. Specimens: main mass with finder; type specimen, 184 g, NHMV.







青藏大卫 发表于 2020-3-13 18:14:55

感谢资料分享,楼主辛苦了!

梦回的流星 发表于 2020-3-14 10:12:03

楼主辛苦
感谢分享

星辰陨石 发表于 2020-3-14 13:15:55

谢谢分享,学习了

有朋至远方来 发表于 2020-8-6 16:47:16

学习了,说真的,如果没有官方的认可,这东西我一看就丢了。:lol

何腊拥 发表于 2020-8-11 16:56:07

这样的我也有

润棠旭棠 发表于 2020-8-24 10:27:09

何腊拥 发表于 2020-8-11 16:56
这样的我也有

很多是表面相似,本质完全不同啊。你的那个的密度是多少的?

居野君 发表于 2020-9-3 19:07:02

阿根廷农民犁地犁出来的,深灰色的融壳。感觉一捏就碎了,颠覆了对陨石的认识。
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