What is another word for rare-earth element?
Pronunciation: [ɹˈe͡əɹˈɜːθ ˈɛlɪmənt] (IPA) 
Rare-earth elements (REEs) are a group of metallic chemical elements that are essential components of many modern technologies, from smartphones and laptops to renewable energy technologies and defense systems. Synonyms for the term "rare-earth element" include lanthanides, rare earths, rare-earth metals, and rare-earth oxides. Lanthanides are elements with atomic numbers 57 to 71, including lanthanum, cerium, praseodymium, europium, and many others. Rare earths are also known as the lanthanide series because they follow the element lanthanum. Rare-earth metals, such as neodymium, samarium, and dysprosium, are used in magnets, lasers, and lighting. Rare-earth oxides are compounds containing rare-earth elements and oxygen.
