Dilithium Crystals

As the key element in all Federation warp engine designs, the dilithium crystal mediates the reaction between the matter and anti-matter in a starship's main engine core.

Dilithium is the only material known to be non-reactive with antimatter when subjected to a high frequency electromagnetic (EM) field, rendering it "porous" to antihydrogen.

Dilithium permits antimatter to pass directly through it's crystalline structure without actually coming into contact with it, due to a field dynamo effect.

Once found only in nature, the technology of the 24th Century antieutectics enables the formation of pure, synthesized dilithium and dilithium matrix re-crystallization through the use of high energy photon injection.