*As the key element in all Federation warp engine designs, the dilithium crystal mediates the reaction between the matter and antimatter in the U.S.S. Enterprise's main engine core. Dilithium is the only material known to be non-reactive with antimatter when subjected to a high-frequency electromagnetic (EMI field, rendering it "porous" to antihydrogen. Dilithium permits antimatter to pass directly through its crystalline structure without actually coming into contact with it, due to a field dynamo effect. Once found only in nature, the technology of 24th Century antieutectics enables the formation of pure, synthesized dilithium and dilithium matrix re-crystallization through the use of high-energy photon injection. *Source: Back of card