[Effect of Raw Materials and Preparing Process on the Composition of Lime-Ash].

As the saying goes that "no ash, no glaze", lime-ash has been the core material widely used to prepare glaze in ancient China. Among all the lime-ashes, those made in Jingdezhen are the most influential and representative ones. Not only did lime-ash contribute greatly to the prosperity of porcelain making of Jingdezhen in Song, Yuan, Ming and Qing Dynasty, but also it has a complicated, rigorous and a touch of "mysterious" in its preparation process, technical principle and glaze mechanism. Therefore, the research of the lime-ash has been an important subject in exploring the "secret" of ancient Chinese porcelain production by Chinese and foreign researchers. In this paper, four representative firewood and two lime stones as the raw materials were collected for the comparative studies, and three kinds of lime-ash with different smolder times were collected from one of the only two traditional lime-ash workshops in Shou'an town nearby Jingdezhen urban area. The chemical composition and phase composition of the raw materials and lime-ash with different smolder times made in Jingdezhen were discussed by testing with the Energy Dispersive X Ray Fluorescence (EDXRF) and X-Ray Diffraction (XRD). The results showed that Fe(2)O(3), MnO contents reaches 1.41% and 1.52% respectively, but the P(2)O(5) content is just 0.54% of Langqi grass which is lower than other firewood that is not only benefited to form the characteristic of "Green in the white" in Jingdezhen traditional glaze, but also is favor to enhance the transparency of glaze and promote the coloration of traditional under-glazed color painted porcelain, such as the blue and white porcelain. The CaO content of grey lime stone is lower than that of the black lime stone with MgO content of 35.79%.This could be the main reason why the craftsmen prefer to use black lime stone to prepare lime-ash. In addition, the EDXRF results show that the K(2)O, P(2)O(5), MnO and Fe(2)O(3) contents have increased as the time of smoldering increases. In the meanwhile, the calcium carbonate (CaCO(3)) phase has also increased, but the calcium hydroxide (Ca(OH)(2)) phase has decreased. The study helps Jingdezhen porcelain "look like jade" and is also good to avoid the "thickness" of glaze when there is a certain amount of Ca(OH)(2) in glaze. So it could be concluded that the unique raw materials and smolder technology of the lime-ash which have provided the technical support for the development of lime-ash glaze are the unique features of ancient Jingdezhen ash glaze.

[Raman and EDXRF Study on Overglaze Decorations of Jingdezhen Ceramics].

Overglaze decoration porcelain is an important category of ancient Chinese ceramics, which has significant artistic value and scientific value. Nondestructive analysis methods such as Raman spectroscopy and EDXRF were used to analyze the overglaze decorations on the Jingdezhen ceramic samples of Yuan, Ming and Qing Dynasty. The recipe and color mechanism of the overglaze pigments were discussed according to the chemical composition and phase composition analysis. The study found that dark red overglaze decorations of ancient Honglvcai, Wucai and famille rose in Jingdezhen are colored by hematite, yellow color is lead tin yellow, carmine decoration is colored by gold less than 0. 1 % in concentration, and green decorations are colored by bivalent copper ion. The result also indicates that the effective combination of Raman spectroscopy and EDXRF can play an important role in the deep research on ceramic artifacts, especially for the overglaze decoration pigments which are interveined each other.

[Chemical composition and chromaticity characteristic of purple-gold glaze of Jingdezhen imperial kiln].

Color glaze is one of the four famous traditional ceramics of Jingdezhen, especially for the products from Ming and Qing Dynasties' official kilns which have rich connotation of technology and culture. The chemical composition and chromaticity characteristic of glaze and body of purple-gold glaze samples from Jingdezhen Ming and Qing Dynasties' official kilns were analyzed by energy dispersive X ray fluorescence (EDXRF) and colorimeter. Preliminary study on the composition, formula and chromaticity characteristic of glaze of purple-gold glaze samples of different period was carried out and the intrinsic causes of ifferences were discussed. The result shows that the concentration of magnesium and calcium in purple-gold glaze is different from the other glazes in Jingdezhen in the same time, probably due to the addition of auburn or brown limestone which is rich in magnesium. The purple-gold glaze sample of Ming Dynasty is darker chiefly because the concentration of magnesium and calcium is higher than the sample of Ming Dynasty which led to iron crystal separated, reducing the brightness and glossiness of glaze. In addition, the body of purple-gold glaze samples from Jingdezhen Ming and Qing Dynasties' official kilns has the characteristics of high silicon and low aluminum and the molar ratio of silicon to aluminum of samples from Ming Dynasty to Qing Dynasty declined, showing that the concentration of kaolin of sample's body of Ming dynasty was increased. The result of this experiment fill deficiency in the ceramic science and technology research in our country about purple-gold glaze from Ming and Qing Dynasties' official kilns and provides scientific material for comprehensive understanding of porcelain marking technology and intrinsic value of Jingdezhen official kiln.

[Research on the composition characteristics of imitated Longquan celadon in Jingdezhen and Longquan celadon].

Longquan celadon not only has been loved widely by the domestic and international ceramic lovers, but also imitated by the kiln workers from different places. Among all of the imitated celadons, the most representative products appeared in Ming and Qing dynasties. This paper used EDXRF to test 38 pieces of Longquan celadon of Song, Yuan and Ming dynasty and imitated Longquan celadon in Jingdezhen of Ming dynasty, combined with firing temperature in order to analyze the different composition characteristics of the bodies and the glaze, evolution rule and formation reasons of these samples in the two different places from the views of time and space. It will be contributed to realising the evolution development, mutual communication and influence of the southern celadon and also provide a scientific basis to get the exact information of the celadon including its time and place of origin and so on.

[Chemical composition and chromaticity characteristic of Jilan glaze of Ming and Qing official kilns].

Color glazes of Ming and Qing official kilns are excellent representatives of the famous ancient Chinese porcelains. The study of official ware with Jilan glaze has been an important topic. But it made slow progress due to the rarity of samples with strict production management and using system. The recipes, chemical composition and chromaticity characteristic of the Jilan samples excavated from official kilns in the Ming and Qing dynasties were first discussed by systematical testing with the energy dispersive X-ray fluorescence (EDXRF) and color difference meter. The results showed that the porcelain stone content in Jilan bodies of official kiln in the Ming dynasty is higher than the samples of the Qing dynasty. The manganese content in Jilan glazes of the Ming dynasty is higher than that in the Qing dynasty, while the glaze ash addition and the lightness value in the glaze are opposite.

[Research on the composition characteristics of Chinese ancient southern white porcelain].

The southern white porcelain is the rise in our country's pottery, it is later than the development of northern white porcelain, but it is rising stars, blockbuster, well-grounded, keeping continuous. Jingdezhen kiln and Dehua kiln are the most representative kilns among the southern white porcelain kilns. the present paper used EDXRF to test 30 pieces of Song, Yuan and Ming period' Dehua white porcelains and Jingdezhen Yuan dynasty Shufu white porcelains samples to analyze the different characteristics of the bodies and the glaze of these samples in terms of time and space. The results show that in the bodies and the glaze of Jingdezhen Shufu white porcelains the iron content is obviously on the high side, and the Dehua white porcelains' potassium content is obviously on the high side, and along with time development they have been in a rising trend, which should be the main reason for the sudden rise of Dehua white porcelain sculptures.

[EDXRF study on the chemical composition and raw material recipe of Jindezhen porcelains in the five dynasties].

Early crafts of porcelain making in Jindezhen were an important issue in ceramic history of China. The chemical composition of white porcelain and celadon samples excavated from Xianghu Kiln in the five dynasties was analyzed using energy dispersive X-ray fluorescence (EDXRF). Raw material recipes of the samples were discussed. The results showed that white porcelain bodies of Xianghu Kiln in the Five Dynasties were made from porcelain stone, while celadon bodies were made from porcelain stone and Zijin clay. Glaze ash and glaze stone were both used in the formula of white porcelain and celadon glaze, and the amount of glaze ash in the celadon was higher than that in the white porcelain samples.