1992年中国古代科技发明发现(第1组)纪念银币1公斤铸铜术 NGC PF 67
CHINA. 200 Yuan (Kilo), 1992.KM-421. Inventions and Discoveries Series, bronze casting. Mintage of 250 pieces.NGC PROOF-67 ULTRA CAMEO.
1992年中国古代科技发明发现(第1组)纪念银币1公斤铸铜术 NGC PF 67
CHINA. 200 Yuan (Kilo), 1992.KM-421. Inventions and Discoveries Series, bronze casting. Mintage of 250 pieces.NGC PROOF-67 ULTRA CAMEO.