AMPHON, R. GEMOLOGICAL AND SPECTROSCOPIC PROPERTIES OF BLUE SAPPHIRES FROM DEN CHAI DISTRICT, PHRAE PROVINCE. Suranaree Journal of Science and Technology, [S. l.], v. 23, n. 2, p. 141–145, 2026. Disponível em: https://ph04.tci-thaijo.org/index.php/SUJST/article/view/14190. Acesso em: 16 sep. 2026.