Prothium

The first underground network of rakghouls was discovered when a mining crew drilled into what they thought was a pocket of prothium gas.

Over four hundred years before the Galactic Civil War, the Hutt artist Gorgo used super-cooled prothium gas to create decelerated luminescent images. By the time of the Galactic Empire, only a few examples of the work remained.

The gas giant Killaniri in the Killaniri system was a major source of prothium. BlasTech Industries maintained a prothium refining station in orbit to process gas mined from the planet using automated gas collectors. The gas was then shipped from starport on the moon, Justa.