Exatanium
Exatanium was a metallic alloy used by some species in outer shell of spacecraft. 

The  claiming to be Steth told Tom Paris a story where he was testing a prototype ship with an exatanium fuselage, which he described had "holes in it" after a phaser-fight with the Entabans. He 'limped' back to Benthos where they helped him repair his vessel. ()

de: Exatanium
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