The term “Rare Earth Elements” (REEs) is one of the biggest misnomers in geology. They are not particularly rare in the Earth’s crust-some are more abundant than copper or lead. However, they are rarely found in concentrated, economically minable deposits. They almost always occur together, clumped in complex mineral structures, making their separation and processing a difficult and expensive chemical challenge.
There are exactly 17 of these elements forming the backbone of modern technology:
- The Lanthanide Series: 15 elements ranging from atomic number 57 (Lanthanum) to 71 (Lutetium).
- The Transition Metals: Scandium and Yttrium, which share similar chemical properties and often occur in the same ore deposits.
REEs are often categorized into “Lights” (more abundant, usually lower value) and “Heavies” (less abundant, critical for advanced applications, higher value).
From the strongest permanent magnets that power electric vehicles and wind turbines to the phosphors in our screens and the catalysts in our industrial processes, these 17 elements are indispensable to the high-tech and green energy transitions.
Below is a deep dive into each of the 17 building blocks of the modern world.