Rubindium
Rubindium is an element found in crystalline form, used in subcutaneous transponders and other communications technology. It could also be used to emit a powerful laser beam.

While Captain Kirk and Spock were imprisoned on Ekos in 2268, Spock used rubindium crystals from the transponders implanted in their arms to improvise a crude, makeshift, and primitive laser cutting torch to escape. ()

Rubindium was necessary in the construction of the 23rd century 's transtator, making both internal and external communications possible. When the 's transtator was damaged beyond repair in 3189, they were not carrying enough rubindium on board to reconstruct it, though a nearby settlement on The Colony had an ample supply of it. ()

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Elements