Bernalium

Bernalium was a mineral. It was used to power the X-ray laser on Space Station W3. (TV: The Wheel in Space)

Bernalium was very rare in the Sol system. The hull of the Arkive was made of a bernalium alloy; when it formed the core of Mnemosyne, the bernalium seeped into the moon. (PROSE: The Wheel of Ice)