First Gram of Yellowcake From Seawater (IMAGE) DOE/Pacific Northwest National Laboratory Caption This first gram of yellowcake was produced from uranium captured from seawater with modified yarn. Chien Wai and colleagues at LCW Supercritical Technologies produced the yellowcake, a powdered form of uranium used to produce fuel for nuclear power production. Credit LCW Supercritical Technologies Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.