CRYSTALS-1616212

Portable energy-dispersive X-ray fluorescence spectroscopy (PXRF, OURSTEX 100FA, OURSTEX, Japan) was applied to analyze the chemical composition of glaze and body of the HF sample (the concentration of light elements such as Na and Mg can be measured by this PXRF instrument[27,28]). It was equipped with a low-vacuum sample chamber, can effectively reduce the absorption of characteristic spectra of light elements in air.Synchrotron X-ray absorption near-edge spectroscopy (XANES) was employed to identify the valence state of iron in the Hare’s fur glaze. The Fe K-edge XANES spectra were collected at the beam line station BL15U1, Shanghai Synchrotron Radiation Facility (SSRF), Chinese Academy of Sciences, China. In this experiment, XANES spectra were obtained in the fluorescence yield mode together with Lytle detector. 28 points were measured with a scanning step of 50 μm, the acquisition time of each energy point was 2 s. Particularly, the scanning area was approximately in the range of 7050-7349.5 eV and the step size was 0.5 eV. The surface morphology of the porcelain sample was firstly examined by optical microscope equipped with an ultra-depth-of-field system (OM, VHX-50000, Keyence, Japan). Images can be taken with a magnification ranging from ×20 to ×1000. The microstructure and elemental composition of crystals in glaze were performed by scanning electron microscope (SEM) fixed with energy-dispersive X-ray spectroscopy (EDS) operated in back scattered electron image mode (TM3000, HITACHI, Japan). Secondary electron images with higher magnification were obtained by another SEM equipment (SU8220, HITACHI, Japan).The information on phase constituents of glaze was characterized by an X-ray diffractometer (XRD, D/max 2550V, Rigaku, Japan) with filtered Cu Kα (40 kV, 40 mA) radiation at a scan rate of 0.5° min−1 in the 2θ range of 20-80°. The Raman spectra were collected using a Laser Confocal Micro-Raman spectrometer (LabRAM XploRA, Horiba, France), and a diode near-infrared (NIR) (532 nm) laser was used for the excitation.