Question: what are the rare earth metals used for?
Answer: Neodymium. This is used to make powerful magnets used in loudspeakers and computer hard drives to enable them to be smaller and more efficient. ... 
Lanthanum. This element is used in camera and telescope lenses. ... 
Cerium. ... 
Praseodymium. ... 
Gadolinium. ... 
Yttrium, terbium, europium.