William H. Gross was a famous stamp collector, and this 2 cents Hawaiian Missionary stamp was the most valuable stamp in his collection. The stamp, dating back to 1851, went for $619,500 at a ...

In 1995, a 2-cent Blue Hawaiian Missionary stamp sold ... making them exceptionally rare. One of these stamps sold at auction for €1.26 million (about $1.73 million after closing costs).