Abstract:
In this study, the apatites containing directional arrangement inclusions from Madagascar were investigated using microscope, Raman spectroscopy, scanning electron microscope (SEM), X-ray energy dispersive spectroscopy (EDS), and magnetic test. Microscopic observation results show that there are abundant needle-like inclusions with metallic luster, which are parallel to
c-axis of the apatite crystal. These inclusions could produce the cat's eye effect of apatite under the light. EDS results reveal that Fe and O elements are rich in the exposed region of inclusion, suggesting that it is a type of iron oxide. Raman spectroscopy displays a weak peak at 662 cm
-1, which can be attributed to the A
1g vibration mode of magnetite. The hysteresis loop test confirms that the inclusions are ferromagnetic substances, indicating that the needle-like inclusions are magnetite.