Chemical-Elemental, Phase Compositions and Porosity Structure of Ceramic Samples from Cham Tower (Vietnam) More Than 1000 Y/O

Elemental analysis of more than 1000 y/o ceramic samples has shown that the primary chemical elements are (%): samples from the exterior part of the bricks - 24.45 Si; 14.31 Ca; 12.68 C; 11.55 Al; 5.60 Fe; 4.29 K; samples from the interior part of the bricks-32.23 Si; 17.66 Al; 12.66 Fe; 5.52 K; 3.07 C; 1.36 Ti; 1.34 C; inclusions in bricks - 53.11 A; 13.40 Ca; 5.46 Si; 3.08 Al; 2.63 K; 1.78 Fe. X-ray phase analysis and electron microscopic methods of analysis showed that the strength properties of the ceramic samples are due to mullite, anorthite, and wollastonite. In addition, the presence of closed porosity in ceramic samples with pores of isometric and oval shapes increases longevity.