ANCIENT GLASS TECHNIQUES AND COMPOSITIONS BY X-RAY OPTICAL METHODS

本研究用X射线光学方法阐明了古代玻璃的化学成分和制造工艺。为了考察管状微珠、逗号状微珠和微珠的制造工艺，本研究在日本首次用高能X射线计算机断层扫描技术显示了微珠的内部结构。同时，用传统的X射线摄影结合新开发的图像处理技术对结构简单的微珠进行了研究。结果表明，弥生时期分布的由钾盐-硅酸盐玻璃制成的管状微珠被掏空，这些玻璃物体发现于福井、京都北部、鸟取县、岛根县，从北久到三宁区肆虐，而不是在九州区。同时，这些玻璃微珠是由钾盐-硅酸盐玻璃制成的，分布于京都北部、鸟取、岛根县，从北久到三宁区，而不是九州区与钾硅玻璃管珠的制造工艺不同，采用模压法制备了分布在同一Yayoi时期的铅钡玻璃管珠。弥生时期的玻璃成分以铅钡玻璃和钾硅玻璃为主。从弥合后期到古丰初，钠钙硅玻璃出现，并在古丰时期达到顶峰。根据氧化铝的含量，日本分布着两种钠钙硅玻璃。据说，古丰时期出现了各种颜色的玻璃，这是由于使用了含有大量铝的钠钙硅玻璃。进一步的研究表明，上述情况在九州北部弥生晚期就已经观察到了。此外，在古丰遗迹中挖掘出了混碱硅玻璃，需要进一步调查，例如制造技术是从哪里带来的。

This study clarified chemical compositions and manufacturing technique of ancient glasses by using X-ray optics.1). To examine manufacturing technique of tubular beads, comma shaped beads, and beads, this study showed inside structure of the beads, using high energy X-ray computerized tomography for the first time in Japan.At the same time, beads that has simple structure were investigated by traditional X-ray photography accompanied with newly developed image processing.The result is that tubular beads, made of potash-silica glass and distributed in Yayoi period were hollowed, and that these glass objects were found in Fukui, northern part of Kyoto, Tottori, Shimane prefectures, raging from Hokuriku to Sannin districts, not in Kyushu district.Meanwhile, tubular beads made of lead-barium glass and distributed in the same Yayoi period were fabricated by molding, which is different from the manufacturing process of tubular beads made of potash-silica glass.2). As for glass compositions in Yayoi period, the majority was lead-barium glass and potash-silica glass. From the latter half of the Yayoi period to the beginning of Kofun period, soda-lime-silica glass appeared, and became at its best in the Kofun period.By the content of alumina, there are two types of soda-lime-silica glasses distributed in Japan.It is said that the glasses with various colors appeared in the Kofun period, which were brought by the use of soda-lime-silica glass containing a large amount of alumina.Further investigation showed that mentioned above were already observed in the northern part of Kyushu from the late Yayoi period.What is more, mixed-alkali-silica glass was excavated in the relic of Kofun period, being needed further investigation, such as from where the manufacturing technique was brought to.