X-ray spectroscopy study on Thai amulet of Phra Kru Nadune Krit Won-in, Chatdanai Boonruang, Udomrat Tippawan, Chome Thongleurm and Pisutti Dararutana EPJ Web Conf., 261 (2022) 04003 Published online: 11 April 2022 DOI: 10.1051/epjconf/202226104003