Beryllium

Beryllium was an explosive substance which could be used as fuel in explosive devices. Due to the fact it created white colored explosions when used, the Mandalorian demolitions specialist and artist Sabine Wren used it as fuel when creating "art" with her explosives. During her time on the starship Ghost, Wren included beryllium in a list of fuels she used in one of her art journals.

Behind the scenes
Beryllium was first mentioned in Sabine My Rebel Sketchbook, a reference book written by Daniel Wallace and published in 2015.