Composition Determination and Cathodoluminescence of Natural Apatite from Different Phosphate Deposits in Northern China

摘要

Two kinds of natural apatite minerals were obtained from two different phosphate deposits in northern China, FanShan, Hebei province and HeiYingShan, Inner Mongolia province. Their chemical compositions, phase structure, and cathodoluminescence (CL) have been comparatively investigated. X-ray diffraction (XRD) analysis indicated that the raw phosphate minerals from Fan-Shan mainly are composed of FanShan apatite (FA) and FanShan mica, respectively, while the ore sample from HeiYingShan contained HeiYingshan apatite (HA) and HeiYingshan magnetite. The mineralogical characteristics and crystal structure of FA and HA were further determined by XRD, scanning electron microscopy, x-ray fluorescence spectrometer, and inductively coupled plasma-mass spectrometry, respectively. These results indicate that FA belongs to fluorapatite, while the HA belongs to hydroxyapatite. The existence of some trace elements has also been verified by the measured CL spectrum. The origin of the observed CL peaks has been discussed, and the relationship of the CL and the chemical composition has also been investigated.