yellowcake is not sulphur

Composition[edit]

Early yellowcake compositions were not well characterized. As late as 1970, the U.S. Bureau of Mines defined yellowcake simply as the final precipitate from the milling process, presumed to be ammonium diuranate or sodium diuranate. The actual composition varies significantly based on leaching agents and precipitation conditions. Identified compounds in yellowcake include uranyl hydroxide, uranyl sulfate, sodium para-uranate, and uranyl peroxide, along with various uranium oxides. Contemporary yellowcake typically consists of 70% to 90% triuranium octoxide (U3O8) by weight, with other oxides such as uranium dioxide (UO2) and uranium trioxide (UO3) also present.[4]