Rare Earth Elements (REE)
The 17-element complex defining the clean energy transition. From high-volume magnet workhorses to specialized defense additives.
What are rare earth elements?
Rare earth elements (REE) form a group of 17 chemically similar metallic elements. This group includes the 15 lanthanides on the periodic table (atomic numbers 57 through 71), plus yttrium (39) and scandium (21), which share similar chemical properties and frequently occur in the same geologic deposits.
Because their electron configurations are uniquely suited to interacting with magnetic fields and light, rare earths are irreplaceable in permanent magnets, phosphors, lasers, and advanced alloys.
Why are they called "rare"?
Despite the name, most rare earth elements are relatively abundant in the Earth's crust—cerium is more abundant than copper. They are considered "rare" because they rarely concentrate into economically viable ore deposits. When they do, they are tightly mixed together, requiring complex, chemically intensive separation processes to isolate individual elements.
Why do they matter?
Rare earth elements are the structural chokepoint of the modern energy transition. Neodymium and praseodymium form the strongest permanent magnets available, driving electric vehicle motors and wind turbines. Heavy rare earths like dysprosium and terbium let those magnets survive extreme heat. The entire supply chain is heavily concentrated, making them highly strategic.
The Two Families: Light vs. Heavy
Geologically and commercially, the 17 elements are broadly divided into two groups. This division dictates mine economics, separation techniques, and supply chain vulnerability.
LREEs
Light Rare EarthsThe high-volume workhorses of the rare earth complex — abundant, magnet-critical, and geopolitically charged.
HREEs
Heavy Rare EarthsScarce, supply-constrained, and irreplaceable — the elements that decide whether magnets survive heat.
Applied Markets: The Magnet Chain
The overarching economic driver for the entire rare earth sector is the permanent magnet. Discover how the materials combine to build EV motors and defense systems.
The Complete Encyclopaedia
Explore the fundamental properties, specialized applications, and market contexts for all 17 rare earth elements.