Over the many thousands of years of the Jedi Order’s existence, there was a constant search to improve and collect better Kyber crystals to power their lightsabres. Despite being in a time of relative peace, the Jedi always wanted to be ready for the threat of Sith return.
In doing so, some young Jedi discovered a cold and even FREEZING Kyber crystal on the planet, called the permaforst crystal. When used inside of a lightsaber, it passed on it’s cold form by giving off an icy blue color and produced a visible chilling effect. The unqiue thing about the permafrost crystal however was that once a Jedi placed it into his lightsaber, it would fuse with that person for all of eternity. It could then only ever be used by that Jedi.
If you tried to use this permafrost crystal with anyone else’s lightsaber it would probably destroy itself… or much worse. The only known source of these crystals came from the deepest layers of the planet Hoth, but how they were actually created remains a mystery. So let me know in the comments if you’d use one of these, knowing it was bound to your sould forever and I will see you in the next one!