Since it was found in 1911, an Egyptian iron bead has sparked wonder and debate over how it was produced — made around 3,300 BC, it predates the region's first known iron smelting by thousands of years. Now, researchers say the iron was made in space and delivered to Earth via meteorite.

"Tube-shaped beads excavated from grave pits at the prehistoric Gerzeh cemetery, approximately 3300 BCE, represent the earliest known use of iron in Egypt," the scientists write in the May 20 issue of .

Early studies of the beads found their iron to be rich in nickel, a key indicator that the metal originated from a meteorite. But researchers contested that idea in the 1980s, suggesting the metal was instead the result of early attempts at smelting....