Jakmanite 632
Jakmanite 632, or just jakmanite, was a substance that was not normally picked up by the sensors of a  starship. This substance, which had no naturally occurring sources, was the radioisotope byproduct of high-energy yurium decay.

Furthermore, along with invidium, saltzgadum, selgninaem, and lucovexitrin, it was one of only five undetectable substances that could exist in a nitrogen-oxygen atmosphere, and which could alter the molecular structure of glass. 

Jakmanite had a half-life of about fifteen seconds and was thereby ruled out as having caused the malfunctions aboard the  in 2366, as there would not have been enough time to spread the substance all over the ship. ()

ja:ジャクマナイト
Materials
Geology
Radiation