Rare earth elements, as the term implies, are elements that are mined. There are 17 types and many of them appear together. After they are extracted, they are refined and generally processed into metals or alloys that have wide application–some in quite small quantities, and many in high tech devices: smart phones, digital cameras, batteries, hard discs, fluorescent lighting, TVs, computers and much more. Significant defense applications include electronic displays, guidance systems, lasers, radar, and sonar systems. The amount of rare earth elements (REE) used in each product may not be a significant part of the product by weight, value, or volume, but without them, the product would not be functional. They are vital to large swaths of technology.

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