Dilithum ore is a type of substance, a mineral ore which contains dilithium mixed with other deposits.
History and specifics[]
Dilithium ore can be mined and processed to remove other types of deposits and yield dilithium that is pure enough to be useful.
During the 23rd century Battle of Artaleirh in the 2270s decade, around the year 2276, dilithium ore was used to military effect in the asteroid belt of the Artaleirh star system. The Constitution II-class Federation starship Enterprise destroyed the Romulan super-heavy cruiser Esemar by detonating a volatile dilithium ore-rich patch of asteroids (TOS - Rihannsu novel: The Empty Chair)
In the 24th century, Federation mining stations specialized in processing dilithium ore. (ST video games: Armada, Armada II)