When measured by total known recoverable underground mineral resources, Australia is the richest country in the world in terms of uranium deposits, possessing roughly twenty-eight percent of the planet's total known uranium reserves. A massive portion of these domestic reserves is concentrated at the Olympic Dam mine located in South Australia, alongside other major deposits. However, when evaluating actual annual commercial production volume rather than raw reserves in the ground, Kazakhstan leads the global market by a wide margin, accounting for over forty percent of worldwide mined uranium output through its state-owned enterprise Kazatomprom. Other nations holding major proven reserves include Canada, Russia, Namibia, and Niger.