The most complicated and rare stamp of the entire Continental Bank Note Issue is the 24-cent General Winfield Scott. Philatelic specialists have contested the actual issuance of this stamp. Support for the CBNCo-printed 24-cent Scott was largely speculative. Those assenters had to assume that the terms of the Post Office Department contract, which set delivery dates and printing production levels for each stamp issue (following the transfer of the original National Bank Note plates to Continental), had been met. After all, Continental had printed stamps for all the other denominations. Still, supporters acknowledged that the CBNCo printing was probably very small; because they also believed that Continental had acquired a large, existing quantity of the 24-cent Scott stamps from National Bank Note Company when it purchased their equipment in 1873.
Continental had apparently not engraved a distinguishing 'secret mark' on this National Bank Note printing plate. And no obvious indication of ownership could be determined by studying the color varieties since the shades were too indistinct. Specialists finally had a break through when a paper variety known as 'ribbed paper' was attributed to Continental Bank Note Company. No other company contracted to print United States stamps had used this paper. The ribbing is a series of either small vertical or horizontal lines in the paper of the stamps.
It was not until the 1960s that a single 24-cent Scott was finally attributed to CBNCo based on a positive identification of the paper. The 24-cent Continental stamp was likely used in combination with other stamps to pay larger foreign destination rates. The fact that there is only one known example makes the 24-cent Scott Continental Bank Note Company Issue the rarest stamp in United States Philately!