Many old vintage watches—especially military watches—have gold or white-ish colored paint on their hands or the numbers on their dials.  This paint could potentially be made of a phosphorescent compound mixed with radium.  This compound would cause the hands/numbers to glow in the dark.  This type of mixture was often chosen over others because of the superiority of its glow and longevity—unlike any other glow-in-the-dark paints, the radium-mixed paint could.. Read More