Yellowcake
Carnotite is a source of uranium. Yellowcake is actually not the carnotite ore but the extract from it, and the intermediate step before fuel fabrication or uranium enrichment. The name comes from the yellow in the original ore and early processing to extract uranium, but in modern processes it is brown or black by the time it has been processed. Carnotite is mined for its uranium content and at times in the early 20th century was mined for radium or vanadium. It is named for Marie Adolphe Carnot (18391920), a French mining engineer and chemist. Uranium is one of the more common elements in the Earth's crust, being 40 times more common than silver and 500 times more common than gold.