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The National Ignition Facility crystals begin as a one-inch cube known as a seed crystal, placed in a six-foot-high tank filled with nearly a metric ton of supersaturated potassium dihydrogen phosphate or KDP.
As it rotates on a turntable in the tank, the crystal begins to grow. In just two months, the crystal grows to be as large as 800 pounds; with conventional methods of growing crystals, this process would take nearly two years. When complete, the crystal is carefully removed from the tank. Then it is measured; and finally it is cut into 40 by 40 centimeter plates to be used to focus, transmit and direct laser beams on their way to the NIF target chamber.
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