Uranium ore support a neutron-mediated chain reaction). Uranium, thorium, and potassium are the main elements contributing to natural terrestrial radioactivity. Uranium has the highest atomic weight of the naturally occurring elements and is approximately 70% denser than lead, but not as dense as tungsten, gold, platinum, iridium, or osmium. It is always found combined with other elements. Along with all elements having atomic weights higher than that of iron, it is only naturally formed in supernova explosions. The primary uranium ore mineral is uraninite (UO) (previously known as pitchblende). A range of other uranium minerals can be found in various deposits. These
Minette (ore) low iron content, however, meant that Lotharingian Minette-ore was successively replaced by more highly concentrated imported ores (with iron contents around 60%). As a consequence, more and more mins were closed down. The last pit in Luxembourg, Differdange, closed in 1981, the last French one, at Audun-le-Tiche in the Moselle department did so in 1997. Minette (ore) Minette is a type of mineral deposit, consisting of iron ore of sedimentary origin, found in the south of Luxembourg and in Lorraine. Minette ore was deposited in the Early Jurassic and Middle Jurassic. The term "Minette" came from French miners. It is