Uraninite is a uranium rich ore that contains large amounts of uranium dioxide often mined for use in nulcear rods in nuclear power plants.
When properly cleanse and install in a Lightsaber, it produces a pale green blade known to be a little wider than the standard blade in width by only two millimeters. Due to its radioactive nature, the blade is known to burn much hotter then the average Lightsaber, and reports been to that those who been cut by the blade have been known to show symtoms of radiation poisoning.