Watch List notes:

TANG: Qian Feng, 649-683, AE cash (4.95g), H-14.100, qián feng quán bao, lightly patinated, EF, RR, ex Zhao Quanzhi Collection. This type was cast by the Emperor Gao Zong in the year 666. In an attempt to overcome a shortage of copper, one of the "qian feng" coins was to be equivalent to ten old coins, although its weight of 2.4 zhu was the same as a one cash coin. This led to extensive forgery, and the coin was withdrawn after a year.

Estimate: 250-350 USD