[Raman spectroscopic study of Ming Dynasty bar-tile from Heijing of Lufeng]

Ming dynasty bar-tile from the archaeological site of Heijing (Lufeng of Yunnan Province, China) was analyzed by Raman microscopy, X-ray diffraction and electron probe microscopy (EPMA). It was found that the major components of the tile are SiO2, besides moonstone(KAlSi3O8 var. of K-orthoclase), Na-orthoclase(NaAlSi3 O8 )and an unknown mineral (Al, Fe)3(PO4,VO4)2(OH)3.8H2O etc. The studies revealed that the agglomerant temperature of the bar-tile reached up to 1500 degrees C, indicating that the agglomerant technology of ceramics of Yunnan in the Ming dynasty (before 17 century) already attained a high level. Raman microscopyproves especially excellent in studing antiques. The results show that the facility and reliability of Raman spectroscopy, as anon-destructive unique technique, are suitable for the discrimination between moonstone and K-orthoclase within tile. No other technique tried was successful in its identification. This research demonstrates that only by combining several complementary techniques is possible to conduct comprehensive research on antiques.