Structure, defects and inclusions in natural polycrystalline ballas-type diamonds are studied by complementary techniques: Scanning Electron microscopy, cathodo- and photoluminescence, X-ray diffraction, radiography and fluorescence, infra-red spectroscopy and carbon isotope analyses. Peculiarities of internal structure of some of the samples are explained by growth of the diamonds as volume-filling dendrites. Similarities of structure and mineralogy of trapped inclusions between ballas-type diamonds with fibrous and cuboid diamonds are established. However, significant differences between growth mechanisms of all these varieties exist and are possibly explained by variations in carbon supersaturation and diamond wettability by growth medium.

中文翻译：

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天然 Ballas 型钻石的结构和缺陷：案例研究

天然多晶 Ballas 型钻石的结构、缺陷和内含物通过补充技术进行研究：扫描电子显微镜、阴极和光致发光、X 射线衍射、射线照相和荧光、红外光谱和碳同位素分析。一些样品内部结构的特殊性可以通过金刚石作为体积填充树突的生长来解释。确定了 Ballas 型钻石与纤维和长方体钻石之间夹杂物的结构和矿物学的相似性。然而，所有这些品种的生长机制之间存在显着差异，这可能是由于碳过饱和度和生长介质对金刚石润湿性的变化所致。