Once mined, uranium is milled to produce what is called calcined yellowcake, and then enriched, either at facilities in Canada or overseas, to create fuel for nuclear reactors.

There, the ore gets turned into uranium oxide or what is commonly known as “yellowcake” because of its bright lemony color.

But the body estimated in 2013 that some 6,400 barrels of yellowcake remained in southwestern Libya, and its inspectors have continued efforts to inspect Libyan sites.

Once mined, the ore is converted into yellowcake, which is just concentrated uranium.

The Pyongsan Uranium Concentration Plant and its associated mine are North Korea's only publicly acknowledged source of yellowcake, or uranium ore, according to analysts.