Image of beer revenue stamp, 50c, issue of 1870 Proof on card of the 1/2 barrel, 50-cent Beer Stamp of 1870. This issue had wavy security lines in fugitive ink extending horizontally across the stamp's center. The most common security lines were lilac, Yellow lines are scarcer, and mixed gray-green and yellow ones are the scarcest. Issues were generally printed in red, with the brick variety being scarcer. This example is brick red. Printed by the Bureau of Engraving and Printing on white paper consisting of long blue fibers with watermarked single line multiple IR.