Almost all commercially mined rhenium is retrieved as a by-product of molybdenum mining as rhenium occurs in amounts up to 0.2% in the mineral molybdenite. A discredited rhenium sulfide known as zappinite does not appear to be valid.
Almost all commercially mined rhenium is derived from molybdenum mining, with rhenium typically occurring at concentrations up to 0.2% in the mineral molybdenite. The discredited rhenium sulfide zappinite does not hold any validity.