1915-32 2½c Circular die essay master die impressions, group comprised of seven separate albino impressions deeply embossed on the back of approximately 50x60mm ruled cards, plus eight deeply embossed impressions on the reverse of a single 126x115mm piece of ruled card, the dies being struck so hard that the impressions break the surfaces of the cards, very fine; unlisted in the Undersander book. (Image)

Est. $400-500

1932 Washington Bicentennial master die impressions, a unique group comprised of eighteen master die albino and colored single impression on wove paper roughly the size of an index card, albino impression are comprised of 1c 1st, 2nd (2) and 3rd impressions, 1½c 1st and 3rd impressions, 2c 1st and 2nd impressions and 4c 1st and 5th impressions, while the colored die impressions are 2c 3rd impression in Carmine and 2c 4th to 7th impressions in Orange red; this issue was designed by C.R. Zimmer and William Marchant of the Shaw & Marchant Company of Dayton, Ohio and the master dies were made by John Sinnock and his assistant Adam Pietz at the United States mint in Philadelphia, all these have been attributed to Adam Piets in pencil on the old album pages to which they are hinged, generally very fine and most unusual, likely a unique offering coming to the market now for the first time; none are listed in the Undersander book. (Image)

Est. $2,000-3,000

1929 5c First air post issue master die impression, two deeply embossed albino impressions, one above the other, on 100x133mm piece of wove paper, inscribed in pencil "2nd Impression" at bottom right, very fine and probably unique; Adam Pietz, Assistant Engraver at the Philadelphia Mint engraved the master die in 1928 based on a common design prepared by Shaw & Marchant Co. of Dayton, Ohio; unlisted in the Undersander book. (Image)

Est. $200-300

1929 5c First air post issue master die impression, two deeply embossed albino impressions, one on the front and the other on the reverse of a 2c Carmine circular die entire which has been opened out for display, very fine and probably unique; Adam Pietz, Assistant Engraver at the Philadelphia Mint engraved the master die in 1928 based on a common design prepared by Shaw & Marchant Co. of Dayton, Ohio; unlisted in the Undersander book. (Image)

Est. $200-300