With an average crustal abundance of less than one part per billion, rhenium is one of the rarest elements in Earth’s crust. Most of the world’s known rhenium resource exists within the mineral molybdenite, substituting for molybdenum atoms in the mineral’s crystal lattice.

Rhenium has one of the most surprising and indirect methods of production of any metal. “About 80 percent of the rhenium obtained through mining is recovered from the flue dust produced during the roasting of molybdenite concentrates from porphyry copper deposits.”

Rhenium has few uses, but they are very important uses. Over 80 percent of the rhenium consumed worldwide is used to make the turbine blades of jet engines. These blades must be made from superalloys that can survive in the extreme stress and high-temperature environment of a jet engine. Most of the remaining rhenium is used as a platinum-rhenium catalyst in petroleum refining.