Pb isotopic ratios (208
Pb versus 207
Pb) in Ancient Nara soil samples and reference ore deposits. C (area between solid lines) represents bronze mirrors brought from China during the Eastern Han Dynasty and the Three Kingdoms era (25 to 280 A.D.) with Pb originating from central to southern China; K (dashed line) represents a bronze mirror and swords brought from the Korean Peninsula during the Yayoi era (10 B.C. to 3 A.D.) with Pb originating from the Korean Peninsula (Saito et al. 2002). Data from (1) Saito et al. 2002; (2) Sasaki et al. 1982; (3) Mabuchi and Hirao 1982; and (4) Mabuchi and Hirao 1987.