Four Chinese characters Chong Ning Tong Bao / Blank, large nail mark. 35mm, 10.64 grams. Issued in 1102-1106 AD. Schjoth #621 var.; Hartill 16.399 var. 

The inscription is written in the famous Slender Gold script. Scarce with a nail mark on the reverse. With a tiny original casting hole (almost impossible to see).

The Song Dynasty was a ruling dynasty in China between 960 and 1279; it succeeded the Five Dynasties and Ten Kingdoms Period, and was followed by the Yuan Dynasty. It was the first government in world history to issue banknotes or paper money, and the first Chinese government to establish a permanent standing navy. This dynasty also saw the first known use of gunpowder, as well as first discernment of true north using a compass. 

This coin is unconditionally guaranteed to be authentic