Issued on October 9, 1948, during the height of China's hyperinflation crisis, this stamp is part of the emergency surcharged series converting existing Central Trust printings to gold yuan values. The original 10 cent brown violet stamp depicting Dr. Sun Yat-sen was overprinted at the San Yi Printing Co. with a new value of ½ cent in gold currency using a bold black hand-applied typographic overprint. Printed without gumming and on unwatermarked paper, it was intended for daily use and reflects the collapsing monetary system of the late Nationalist period. The block shown is mint never hinged and extremely fresh, with well-centered impressions and intact margins. Typography and format match known San-i characteristics, including the irregular perforation and characteristic font style. A scarce survivor of a transitional economic episode. Estimate "$70 – 90"