Rare earth elements ("REEs") or rare earth metals are a set of seventeen
chemical elements in the periodic table, specifically the fifteen
lanthanides plus scandium and yttrium. Scandium and yttrium are
considered rare earth elements since they tend to occur in the same ore
deposits as the lanthanides and exhibit similar chemical properties.
Despite their name, rare earth elements (with the exception of the radioactive promethium) are relatively plentiful in the Earth's crust, with cerium being the 25th most abundant element at 68 parts per million (similar to copper). However, because of their geochemical properties, rare earth elements are typically dispersed and not often found in concentrated and economically exploitable forms. The few economically exploitable deposits are known as rare earth minerals. It was the very scarcity of these minerals (previously called "earths") that led to the term "rare earth". The first such mineral discovered was gadolinite, a compound of cerium, yttrium, iron, silicon and other elements.
Rare earth elements are heavier than iron and thus are produced by supernova nucleosynthesis or the s-process in asymptotic giant branch stars. In nature, spontaneous fission of uranium-238 produces trace amounts of radioactive promethium, but most promethium is synthetically produced in nuclear reactors.
Rare earth elements change through time in small quantities (ppm, parts per million), so their proportion can be used for geochronology and dating fossils.
Rare earth pricing
Rare earth elements are not exchange-traded in the same way that precious (for instance, gold and silver) or non-ferrous metals (such as nickel, tin, copper, and aluminum) are. Instead they are sold on the private market, which makes their prices difficult to monitor and track. The 18 elements are not usually sold in their pure form, but instead are distributed in mixtures of varying purity. As such, pricing can vary based on the quantity and quality required by the end user's application.
Cerium Cesium Dysprosium Erbium Europium Lanthanum Gadolinium
Iridium Lutetium Mischmetal Neodymium Praseodymium Samarium
Scandium Terbium Thulium Ytterbium Yttrium Zirconium01
Despite their name, rare earth elements (with the exception of the radioactive promethium) are relatively plentiful in the Earth's crust, with cerium being the 25th most abundant element at 68 parts per million (similar to copper). However, because of their geochemical properties, rare earth elements are typically dispersed and not often found in concentrated and economically exploitable forms. The few economically exploitable deposits are known as rare earth minerals. It was the very scarcity of these minerals (previously called "earths") that led to the term "rare earth". The first such mineral discovered was gadolinite, a compound of cerium, yttrium, iron, silicon and other elements.
Rare earth elements are heavier than iron and thus are produced by supernova nucleosynthesis or the s-process in asymptotic giant branch stars. In nature, spontaneous fission of uranium-238 produces trace amounts of radioactive promethium, but most promethium is synthetically produced in nuclear reactors.
Rare earth elements change through time in small quantities (ppm, parts per million), so their proportion can be used for geochronology and dating fossils.
Rare earth pricing
Rare earth elements are not exchange-traded in the same way that precious (for instance, gold and silver) or non-ferrous metals (such as nickel, tin, copper, and aluminum) are. Instead they are sold on the private market, which makes their prices difficult to monitor and track. The 18 elements are not usually sold in their pure form, but instead are distributed in mixtures of varying purity. As such, pricing can vary based on the quantity and quality required by the end user's application.
Cerium Cesium Dysprosium Erbium Europium Lanthanum Gadolinium
Iridium Lutetium Mischmetal Neodymium Praseodymium Samarium
Scandium Terbium Thulium Ytterbium Yttrium Zirconium01
