Kyber Crystal (Lightsaber Crystal)
At the heart of every Jedi lightsaber is a kyber crystal found on several planets, most notably the icebound caves of Ilum. This crystal is attuned to the Force, and connected to a Jedi Knight on a deeply personal level. In this way, a lightsaber is an extension of a Jedi's Force awareness. Because Jedi let the Force guide their selection of the crystal, the vibration that the crystal creates in the lightsaber blade helps Jedi center themselves and find balance in the Force. In this way, a Jedi can center his or her attention beyond the distractions of combat. A lightsaber crystal is colorless until first attuned and connected to a Jedi -- at which times it glows either blue or green, or in some rare instances, another shade. From that point on, it retains that hue.
History
THE DARK TIMES
While kyber crystals are at the core of every lightsaber, the Empire explored ways to weaponize them for more nefarious purposes. They began to mine for kyber crystals across worlds, and were notably thwarted twice in securing massive crystals by the Ghost crew and Saw Gerrera. But on Jedha they uncovered a surplus of kyber, which would be enough to power their dreaded Death Star.
