25 Pfennig and 50 Pfennig Crown / Eagle with a steep, black printing imprint "Marshall Islands" as a so-called Berlin proof issue, 1898 / 99 produced for exchange and trade purposes of the Imperial Post Office, each as a corner block of four in the upper left (field 1 / 2 and 11 / 12), mint, flawless condition, certified by Bothe BPP and photo certificates Ronald F. Steuer BPP "in perfectly mint condition.", Michel 12. 000.-