Deutronium is a flammable substance resembling white pebbles with many uses. ("The Girl from the Green Dimension")
The Robinsons spent much of their time drilling for deutronium, as they required it as fuel for the Jupiter 2.
Lacking any currency, the Robinsons attempted to buy the freedom of Verda the android with deutronium. Mr. Zumdish said that it would involve considerable expense to refine the substance. ("The Android Machine")