Ionoluminescence spectroscopy and microscopy of lapis lazuli

Natural heterogeneous lapis lazuli has been investigated using the complementary techniques of ionoluminescence spectroscopy, ionoluminescence microscopy and micro-PIXE. The equivalent probed depths, the possibility of simultaneous use and the capability of non-destructive in-air application suggest the combined use of ionoluminescence and micro-PIXE techniques as an appropriate approach in mineral analysis to reveal the texture, chemical composition, and elemental distribution of the samples. In this research work, the various mineral phases of a lapis lazuli sample were detected and analyzed. It was possible to identify most of the minerals in the analyzed area, including apatite, a mineral phase uncommon in lapis lazuli, and point out different luminescence features of crystals of the same mineral, diopside, found in different parts of the same lapis lazuli sample.