The Study on Plaster Materials: Special Reference to Rajagala Cave Dwellings

Abstract

Rajagala is one of the cave-based monasteries, where inhabited by more than a hundred monks from the 2nd century to the 11th century AD, those who practiced meditation in the caves, had done certain construction work to make suitable living place. Some ancient construction works are still visible. This study was conducted to understand the diversity of the construction materials used, and to determine whether there was any guidance from Vinaya Pitaka, it also, emphasized the plaster materials that had been used to construct different caves, particularly eight caves, and plaster sample materials were analyzed by using analytical methods such as microscopic observation, chemical, particle size, cross-section, and Fourier transform Infrared Spectroscopic analysis (FTIR). Furthermore, had done cross reference with literary sources such as Pali Vinaya Pitaka. According to the results, the plasters were frequently made with clay and sand while floor plaster consisted of lime and sand with different ratios. In addition, organic materials such as paddy husk and charcoal particles were identified. The use of both sorted and unsorted sands was observed. In some cave plasters, a charcoal layer had been applied to make a blackish appearance, there were some remaining pigments mainly red and yellow ocher applied on a lime layer, which had been decorated with some paintings. The study identified that the use of the materials they applied for the construction work was to some degree aligned with the code of discipline, particularly in the Senasanakkandaka in Chullawagga in Buddhist doctrine