An extremely rare example of China's 1923 2c on 3c inverted surcharge stamp used on cover is to join the nation's finest philatelic rarities on January 13 in Hong Kong.
Estimated at $451,500-516,000, the cover is one of just two known that bear this variety. It will be accompanied in the auction by the famed 1915 $2 Hall of Classics invert - the only example used on cover - which stands as the top lot of the sale.
The surcharge stamp originates from China's Junk issue, the definitive stamps which were first issued in 1913 featuring an early "junk" ship. The series continued to see usage into the 1930s, with the designs re-engraved in 1923.
The 1923 redesign can be distinguished from the preceding stamps by a number of changed features, including the whitecaps in the water underneath the junk being removed and the water darkened.
The cover features the blue-green variety of the inverted surcharge, tied on a 1924 local Wanhsien registered cover. Also featuring is the Junk 2c yellow-green and 4c slate-grey, with the original registration receipt affixed on the reverse. It will be sold with a 1991 Holcombe Certificate.
Elsewhere in the sale, the largest block of Sinkiang 1915 $1 with transposed characters will be sold from the Colonel Valentine Burkhardt Collection, with a $129,000-193,500 estimate. One of the Four Treasures of the Republic, the six stamps are in magnificent condition with just a couple of split perforations.
The world record for Sinkiang philately was set in December 2012, when an 1879 cover from the province sold for $791,260.