Plutonium dust is an item added by GregTech that is used to make Plutonium Cells. The cells are used in Nuclear Reactors to produce energy. One can use the Automated Canning Machine, also added by Gregtech, to place Plutonium Dust into Empty Cells, thus producing Plutonium Cells suitable for use in fission-powered Nuclear Reactors.
Plutonium Dust can be produced by combining 4 Tiny Piles of Plutonium Dust, which can be obtained by processing Uranium Ore in an Industrial Grinder. Grinding Uranium Ore in Thermal Expansion's Pulverizer also has a small chance of producing Plutonium Dust as an extra item. One can also convert Uranium Dust to Plutonium Dust with the aid of UU-Matter by crafting one Uranium Dust surrounded by 8 pieces of UU-Matter.