10 Dollars Independence, copper-nickel

Belize gained independence from Britain in 1981, but the road there was complicated by Guatemala's long-standing territorial claim over the entire country — a claim backed by a credible military threat that kept British troops stationed in Belize well into the 1990s. The 1991 date on this issue marks the tenth anniversary of independence, celebrated under conditions that were anything but settled; Guatemala only formally recognized Belizean sovereignty that same year, after a decade of diplomatic pressure.