Blockonium

Blockonium is the material that forms the core of a starship drive. It is incredibly valuable; a single 1x1 brick of blockonium is worth ten thousand credits. When Spaceman of Futuron lands on Oasis, he finds the Oasian miners being taxed with huge tributes of blockonium to High Lord Spruesworth. Since Oasis is the sector's main source of the material, Spruesworth is willing to go to great lengths to keep it in his hands, sending an Imperial Knight along to protect it.