Health care is another key industry that relies on rare earths. Imaging techniques such as CAT scans, MRIs, PET imaging devices, digital X-rays and lasers take advantage of the elements’ optical properties.
The biggest medical use for rare earths is in medicine’s biggest magnet–the magnetic resonance imaging (MRI) machine. MRI machines need over 1500 pounds of magnets each. Rare earth magnets are replacing the magnet technology in MRI machines. MRI machines used to use coils of electrical wire cooled in liquid helium, because they were lighter than permanent magnets. But rare earths magnets are lightweight and powerful enough to make that switch feasible.