Abstract Calcium phosphate apatite, Ca5 (PO4)3(OH,F,Cl), is a common accessory mineral in coal seams. Although minor, its role in hosting P and F can reduce the economic viability of coking and thermal coal deposits. Apatite in coal is commonly 1 wt%. However, the small crystallite size of the encrusting-apatites and the pits on the polished surface of the detrital-apatites intermixed with the coal layers hindered determining the halogens by this method. Although, all of the apatites in the coals were able to be analysed by infrared spectroscopy, both the combined kaolinite and apatite spectra, and the noise in the spectra at the lower wavelengths hindered evaluating the F in the apatites using this method. Despite these limitations, the findings of this study show that EPMA is probably the most suitable analytical technique for determining the halogen contents of the different modes of apatites in situ in coal pellets. Future work should focus on determining whether the modes of occurrence reflect paragenesis.

中文翻译：

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煤中磷灰石原位分级技术

摘要 磷酸钙磷灰石Ca5 (PO4)3(OH,F,Cl)是煤层中常见的副矿物。虽然次要，但它在承载 P 和 F 方面的作用会降低炼焦和动力煤矿床的经济可行性。煤中的磷灰石通常为 1 wt%。然而，结壳磷灰石的小晶粒尺寸和碎屑磷灰石抛光表面上的凹坑与煤层混合，阻碍了通过这种方法确定卤素。虽然煤中的所有磷灰石都可以通过红外光谱分析，但高岭石和磷灰石的组合光谱以及较低波长光谱中的噪声阻碍了使用这种方法评估磷灰石中的 F。尽管有这些限制，这项研究的结果表明，EPMA 可能是原位测定煤球团中不同模式磷灰石卤素含量的最合适的分析技术。未来的工作应侧重于确定发生模式是否反映共生。