Lead containing high refractive index glasses have been special materials and very popular for human
beings for several hundreds of years [1-7]. There are many uses of glasses in Thailand, especially for
decoration in the old style that called the Ancient Thai Glass (ATG), as shown in fig. 1 (a). A lot of old
style glasses are found in the middle area of country where we can see in places of special architectural
such as the old palaces and the Buddhist sites which have been the focal point of Thai community
activities for centuries [8]. Many colors of glasses such as colorless, blue, green, red, and amber have
been found. Under the tropical sun, it gives out an artistic harmony of flamboyance and serenity. This
type of glass is very thin with the thickness of about 0.5-2 mm, in Thailand sometimes called Krajok
Kreab. The ancient Thai glass can be classified into two types; the Ayutthaya Glass (A-ATG) and the
Ratanakosin Glass (R-ATG), which made by Thais in the periods of the Ayutthaya and the Early
Ratanakosin Ages during 1310-1767 and 1782-1868 A.D., respectively. In this study, some of the
ancient glass can be collected from the palace and the old temples. Both A-ATG and R-ATG were
investigated for their structures under the scanning electron microscope (SEM). The structure can be
divided into three layers; glass body, binder, and coated metal, as shown in fig. 2 (a). It was also found
that the glass body and the coated metal layers of the R-ATG are thinner and less of bubbles than those
of the A-ATG. The composition of the ATG was analyzed by using wavelength dispersive X-ray
fluorescence spectrometer (WDXRF). The main composition of the glass body is found to be silica and
lead. The X-ray photoelectron spectroscopy analysis (XPS) was used to investigate the composition of
the coated metal and the binder. The coated metal is lead alloy, while the binder is organic compounds.
The measured values of the refractive index (RI) of the ATG are between 1.525 to 1.620 and 1.540 to
1.600 for the colorless and the colored glasses, respectively