60th AUCTION - day 2

China (PRC) - specialities: 1977, phosphorescent stamp trial printings depicting

China (PRC) - specialities

---

1977, phosphorescent stamp trial printings depicting Chinese-made automatic sorting machine in development, one of the eight values on cover, cancelled with machine cancel "Guangdong, Scientific Research", undated and unaddressed, probably made during the experiment of the stamps and the automatic sorting machines. The Chinese postal authorities started its development of phosphorescent stamps from the mid-1970s, and after this trial printing, the technology was used in the T49 Postal Transportation commemorative issue, and the later definitive issue of 1982. Phosphorescent stamps were discontinued afterwards. Phosphorescent trial printings on cover are rarely seen.

---

Condition: Cover