Lot
1045 
Postal Card, 1873, 1¢ brown on buff, Master Die Proof, unwatermarked, showing the secret mark - a small dash of color inside the right angle of the inside frame above the indicia, fresh and Very Fine. Scott No. UX1P. USPCC No. S1Pa $1,000.
The Master Die secret mark is not found on the issued cards, which are watermarked.
Realized: $280