Onyx kyber

Onyx kybers were a very rare type of kyber crystal found on Ilum. When used in a lightsaber, the crystal formed a black blade with a null core that absorbed visible light, resulting in the blade's black coloration. An onyx kyber was used in the Darksaber crafted by Tarre Vizsla, the only known Mandalorian accepted into the Jedi Order.

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