1920 3c Liberty, large die proof in black, reduced to stamp size, with serial number at top, card mounted and inscribed "Experiment," fine and rare (Image)

Est.$500

1920 2c Liberty, die proof in black, with serial number at bottom, card mounted and inscribed "Experiment" and "Specimen", fine (Image)

Est.$500

1920 2c Liberty, vertical strip of five, die proof in black, with serial number at top, card mounted and inscribed "Experiment" and "Specimen", middle stamp defective, otherwise fine and rare (Image)

Est.$750

1930 uncut die proof sheetlet on bond, color chart "Number 26 blue", with serial number at top, v.f. (Image)

Est.$250

1930 uncut die proof sheetlet on bond, color chart "Number 206 brown", with serial number at top, v.f. (Image)

Est.$250

1947 3c-25c black, large die proof, card mounted, color chart "Postage and Revenue Stamps", eight designs (four different) including Communication, Education, Rembrandt and Taj Mahal, each inscribed "Specimen", dated and signed, including "OK for Color", with Engraving Order Dept. date stamp on back, v.f. (Image)

Est.$750

1947 25c Communication, large die proof in green, card mounted, pencil inscriptions indicating color adapted for Haiti airmail stamp, pencil dated 1954, v.f. (Image)

Est.$250