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10. What are critical materials? Many clean energy technologies -- from wind turbines and energy-efficient lighting to electric vehicles and thin-film solar cells -- use materials with magnetic, catalytic and luminescent properties. These materials -- classified as critical by the Energy Department -- are essential to the clean energy economy (they have high demand and limited substitutes) and are at risk for supply disruptions.

9. Basic availability is not the only factor affecting a critical material’s overall supply risk. Other factors include political or regulatory risks in countries that are major producers of critical materials; lack of diversity in producers; and a competing technology demand -- many consumer electronics like mobile phones, computers and TVs use materials essential to clean energy technologies.

8. Critical materials include five rare earth elements -- dysprosium, terbium, europium, neodymium and yttrium. Other elements -- lithium and tellurium -- are projected by the Department to be “near critical” in the next 15 years.

7. In 1787, a Swedish chemist discovered a black mineral he named ytterbite after Ytterby, a village in Sweden. In 1794, a Finnish chemist isolated the first rare earth element -- yttrium -- from ytterbite.

6. Did you know rare earths are not really rare? More abundant than gold, rare earth elements can be found in mineral deposits widely distributed across the earth, including the United States, Canada and Australia. This map shows rare earth deposits around the world.

5. In total, there are 17 rare earth elements, which are highly dispersed in the earth’s geology. Their chemical similarities make them very difficult to economically recover and separate from each other.

4. Magnets that use the critical material neodymium are the most powerful known permanent magnets. These magnets are about 10 times more powerful than your average refrigerator magnet, and are used in some wind turbine generators and electric vehicle motors.

3. Dysprosium is used in permanent magnets -- adding a small percentage of dysprosium to a magnet made using the rare earth element neodymium can increase the magnet's ability to withstand high temperatures and helps reduce demagnetization.

2. The critical materials europium, terbium, and yttrium are used in fluorescent lights as well as flat screen TVs and computer screens. Those elements are responsible for the red, blue and green colors.

1. Recycling, reuse and more efficient use of critical materials could significantly lower world demand for newly extracted materials. Currently, only 1 percent of critical materials are recycled at the end of a product’s life. Among other things, the new Critical Materials Hub will focus on developing more feasible recycling processes.