Dilithium

Dilithium is a rare transperiodic element in the, usually found in crystalline form throughout the galaxy. It is one of the key components of warp drive, regulating the flow of matter and antimatter.

Planets rich in dilithium were of very high strategic importance. Some of those worlds included Coridan, Elas, and Halka. 

The Klingon and Romulan Star Empires both used prisoners to mine dilithium from Rura Penthe and Remus, respectively. 

Dilithium-rich planets near the borders between galactic powers were often sources of contention. Ghioghe, in the Triangle between Federation, Klingon and Romulan space was one, as was Pharos in the Marrat Nebula. (Yesterday's Heroes;  : "")

Dilithium crystals were fragile things, and could crack under severe strain, such as ship-to-ship combat, or a temporal breakaway maneuver. However, Captains Spock and Montgomery Scott devised a method of recrystallizing dilithium while stranded on Earth in 1986 and by the 24th century, dilithium recrystallization had become commonplace aboard Federation starships. 

In the 24th century, Coleman Dynamic Industries and the Dytallix Mining Corporation were leading civilian firms in the Federation dilithium industry.