A special crypto stamp series for the Boston world expo 2026, jointly issued by United Nations Postal Administration, the Universal Postal Union (UPU), Ciphers.me and Royal Joh. Enschedé. This limited serie of 6 cryptostamp sheets has been collaboratively designed and produced by Royal Joh. Enschedé and will be available to visitors. One unique stamp sheet will be issued each day of the exhibition, with each sheet eligible for minting into an NFT on Ciphers.me. If all 6 stamps are minted, your 6th will be transformed into a special golden NFT.