1:45 PM - 3:15 PM
[O11-P77] Clay Analysis of Bricks Excavated from Kuji White Sugar Factory Site, Amami-Oshima Island, Kagoshima Prefecture, Japan
Keywords:clay soil analysis, brick, X-ray fluorescence analysis, white sugar factory, Amami Island
1. Introduction
Kuji Sugar Factory Ruins, Setouchi Town, Oshima County, Kagoshima Prefecture The Kuji Sugar Factory was one of the factories built on Amami Oshima Island at the end of the Edo period. It was designed by Thomas James Waters, who also designed the Ginza Bricktown area, and the brick ruins unearthed during the excavation survey were an important discovery for considering the state of affairs during the introduction of bricks in Japan . On the other hand, it is not clear where the excavated bricks were made. Therefore, in this study, we aim to clarify the place of manufacture by examining the characteristics of the clay body of the excavated bricks using X-ray fluorescence analysis and examining the chemical composition.
2.Data and analysis method
The materials used for the clay analysis were 27 bricks excavated from the site of the former Kuji Sugar Factory in Setouchi Town. The bricks were mainly ordinary bricks, which were classified into four categories from an archaeological perspective, and the parts to be analysed were identified. Elemental analysis was carried out using a wavelength dispersive X-ray fluorescence spectrometer (Rigaku ZSX Primus Ⅱ).
3.Results
The clay body of ordinary bricks that are classified as I-a and I-b in archaeological morphology (the subdivisions of a and b are size differences) is coarse and fragile, while the clay body of ordinary bricks that are classified as II is well-fired and hard.When a two-element distribution diagram was created between the elements analysed, the existence of two distribution bands was confirmed in the Ca-K distribution diagram and the Na-Ca distribution diagram.In the Ca-K distribution diagram, Types I-a and I-b tended to have a high potassium content and a low calcium content. Type Ⅱ tended to have a low potassium content and a high calcium content.
The Na-Ca distribution diagram shows that Type Ⅱ has a higher sodium content than Types I-a and I-b. All of the analyses clearly show that there are significant differences between Types I-a and I-b and Type Ⅱ.
4. Discussion and future issues
The large differences in elemental composition between Types I-a and I-b and Type Ⅱ suggest that they reflect the conditions of the parent rock of the clay. Assuming that the clay used to make the bricks was taken from a nearby source, it is highly likely that the bricks were made in different places. Also, the fact that there are no large differences in elemental composition between Types I-a and I-b suggests that the only difference is in the archaeological form, and it is highly likely that they were made in the same place.
By adding analysis of the chemical characteristics of the host rock in the Kuji area, which is thought to be the basis for future estimates, and analysis of the bricks excavated from the remains of the three other sugar factories scattered around the island, it is hoped that the situation during the introduction of brick production in Japan will become clear.
Kuji Sugar Factory Ruins, Setouchi Town, Oshima County, Kagoshima Prefecture The Kuji Sugar Factory was one of the factories built on Amami Oshima Island at the end of the Edo period. It was designed by Thomas James Waters, who also designed the Ginza Bricktown area, and the brick ruins unearthed during the excavation survey were an important discovery for considering the state of affairs during the introduction of bricks in Japan . On the other hand, it is not clear where the excavated bricks were made. Therefore, in this study, we aim to clarify the place of manufacture by examining the characteristics of the clay body of the excavated bricks using X-ray fluorescence analysis and examining the chemical composition.
2.Data and analysis method
The materials used for the clay analysis were 27 bricks excavated from the site of the former Kuji Sugar Factory in Setouchi Town. The bricks were mainly ordinary bricks, which were classified into four categories from an archaeological perspective, and the parts to be analysed were identified. Elemental analysis was carried out using a wavelength dispersive X-ray fluorescence spectrometer (Rigaku ZSX Primus Ⅱ).
3.Results
The clay body of ordinary bricks that are classified as I-a and I-b in archaeological morphology (the subdivisions of a and b are size differences) is coarse and fragile, while the clay body of ordinary bricks that are classified as II is well-fired and hard.When a two-element distribution diagram was created between the elements analysed, the existence of two distribution bands was confirmed in the Ca-K distribution diagram and the Na-Ca distribution diagram.In the Ca-K distribution diagram, Types I-a and I-b tended to have a high potassium content and a low calcium content. Type Ⅱ tended to have a low potassium content and a high calcium content.
The Na-Ca distribution diagram shows that Type Ⅱ has a higher sodium content than Types I-a and I-b. All of the analyses clearly show that there are significant differences between Types I-a and I-b and Type Ⅱ.
4. Discussion and future issues
The large differences in elemental composition between Types I-a and I-b and Type Ⅱ suggest that they reflect the conditions of the parent rock of the clay. Assuming that the clay used to make the bricks was taken from a nearby source, it is highly likely that the bricks were made in different places. Also, the fact that there are no large differences in elemental composition between Types I-a and I-b suggests that the only difference is in the archaeological form, and it is highly likely that they were made in the same place.
By adding analysis of the chemical characteristics of the host rock in the Kuji area, which is thought to be the basis for future estimates, and analysis of the bricks excavated from the remains of the three other sugar factories scattered around the island, it is hoped that the situation during the introduction of brick production in Japan will become clear.