Identification and characterization of small extraterrestrial samples, such as small Antarctic meteorites <~1 cm, require the development of convenient laboratory‐based nondestructive analytical techniques using X‐ray diffraction (XRD). We explore the characterization criteria using an X‐ray diffractometer with a Gandolfi attachment using sub‐mm small fragments and powder aggregates for various kinds of stony meteorites and develop a new analytical technique. We primarily focus on olivine and pyroxene because they are the most abundant and important minerals for stony meteorite classification. A new calibration is performed to estimate the FeO content of the olivine in unequilibrated ordinary chondrites, which is useful for determining the meteorite chemical group irrespective of powder aggregate diameter but dependent on fragment grain diameter. This is because X‐ray intensity absorption is more effective for grains than for powders. Clinoenstatite (Cen) and orthoenstatite (Oen) were distinguished using the presence or absence of the isolated Oen 511 index peak. The method is also applied to other stony meteorites including carbonaceous chondrites and achondrites. The XRD results are consistent with studies based on polished sections involving textural observations by scanning microscope and chemical compositions of the constituent minerals. The new measurement technique presented here is convenient because of its use in air by the laboratory‐based X‐ray diffractometer, which makes it useful for the initial analyses of restricted extraterrestrial sample characterization.

中文翻译：

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使用Gandolfi附件通过X射线衍射表征小型外星物质的新测量技术

小型外星样本（例如小于1 cm的南极陨石）的鉴定和表征，需要开发使用X射线衍射（XRD）的基于实验室的便捷无损分析技术。我们使用带有Gandolfi附件的X射线衍射仪（使用亚毫米小碎片和各种粉末状聚集体，用于各种石质陨石）探索表征标准，并开发一种新的分析技术。我们主要关注橄榄石和辉石，因为它们是石陨石分类中最丰富，最重要的矿物。进行了新的校准，以估计未平衡的普通球粒陨石中橄榄石的FeO含量，不管粉末聚集体的直径如何，都取决于碎片的粒径，这对于确定陨石的化学基团很有用。这是因为X射线强度吸收对谷物比对粉末更有效。利用存在或不存在孤立的Oen 511指数峰来区分斜硅钙长石（Cen）和正钙长石（Oen）。该方法还适用于其他石质陨石，包括碳质球粒陨石和无定形陨石。XRD结果与基于抛光切片的研究一致，该抛光切片涉及通过扫描显微镜观察的组织观察和组成矿物的化学组成。此处介绍的新测量技术非常方便，因为基于实验室的X射线衍射仪可将其用于空气中，