1 Crown - Elizabeth II Postage Stamp, Silver

Gibraltar's 1990 crown program coincided with the 150th anniversary of the Penny Black, the world's first adhesive postage stamp, issued by Britain in May 1840. The Penny Black's brief run — replaced after less than a year by the Penny Red, whose red ink made cancellation marks harder to see — makes it one of the most storied philatelic objects in existence, and Gibraltar leveraged that anniversary heavily across a series of collector issues.

KM#49a is the sterling silver variant of a base metal type, produced specifically for the proof and collector market rather than circulation.