FIGURE 1 in Fourier transform infrared spectroscopy (FTIR) characteristics of ancient amber artifacts of the Han Dynasty from Hunan, China

FIGURE 1. Possible ancient trade roadmap of both the Eurasian Steppe Silk Road and the Maritime Silk Road. 1, the present Capital, Beijing; 2, the ancient Capital city during the Han Dynasty, Xi'an, Shaanxi Province; 3, Nanyang, Henan Province, where unearthed artifacts of Han Dynasty made by Burmese amber (Chen et al., 2019); 4, Tomb Changchen M010, Changsha, Hunan Province; 5, Tomb Chentie M001, Chenzhou, Hunan Province.