wallpaper
n.— «Morton began collecting stamps as a kid, deciding to specialize in stamps from a particular country. He settled for the Gold Coast, which later became Ghana, and that turned out to be a nightmare when the country turned Communist and issued what collectors refer to as “wallpaper,” he said. Wallpaper is stamps that aren’t used for postage but printed merely for collectors, thus generating revenue beyond the scope of mail postage.» —“Stamp of approval: RR collector finds hobby something he can stick to” by Gary Herron Rio Rancho Observer (New Mexico) Oct. 20, 2006. (source: Double-Tongued Dictionary)
Further reading
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