Rare earth elements are a group of seventeen chemical elements that occur together in the periodic table.  

• The group consists of yttrium and the 15 lanthanide elements (lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium).  
• Scandium is found in most rare earth element deposits and is sometimes classified as a rare earth element.  
• The rare earth elements are all metals and the group is often referred to as the “rare earth metals.”  
• These metals have many similar properties, and that often causes them to be found together in geologic deposits.  

• They are also referred to as “rare earth oxides” because many of them are typically sold as oxide compounds. 
• A large number of alloys are made more durable by the addition of rare earth metals.  
• Glass, granite, marble, and gemstones are often polished with cerium oxide powder. Many motors and generators contain magnets made with rare earth elements.  
• Phosphors used in digital displays, monitors, and televisions are created with rare earth oxides. Most computer, cell phone, and electric vehicle batteries are made with rare earth metals. 

Source: The Hindu