A manmade crystal, also known as a warp drive core, used in a warp drive's energy supply system. Formed by refining exalithium ore, a mineral that does not exist on Earth, into microscopic crystals which are then concentrated and recrystallized. The resulting crystal is then used in a warp drive to create antimatter and annihilate it with matter, producing large quantities of energy. The previous method of creating antimatter on Earth (via an antiproton decelerator) was incapable of producing enough energy for warp travel; the use of exalithium crystals, introduced to Earth by the Eldarians, was the key to building a practical warp drive system.