Neosorium composite

From Memory Alpha, the free Star Trek reference

Neosorium composite is a material based in neosorium Federation technology.

In 2371, B'Elanna Torres realized that the residue of a radiation accident had a .41 percent trace of a neosorium composite, and she didn't know anyone who used neosorium technology except for the Federation. (VOY: "State of Flux")