Proto-Saber

The Proto-Saber, sometimes simply called ancient lightsabers, were the weapons wielded by the Ancient Jedi and Sith before the invention of the crossguard-lightsaber.

They were metallic blades that could be infused with the power of the force by a force-wielder to increase the blade's potency in battle. There were two variations of the Proto-saber; the regular sword and the dagger. While the sword was eventually phased out of use and replaced with the crossguard lightsaber, and shortly after that, the typical lightsaber, the dagger variant would continue to have ritualistic significance in religious groups across the galaxy. For example, the Followers of the Infinite Darkness, a dark-side worshipping cult that existed over 6000 years after the Proto-saber's creation performed indoctrination rituals for new recruits with a Proto-Saber dagger

The Prime Jedi personally created two Proto-Sabers, the Blade of Darkness and the Blade of Light in an attempt to create a personal balance of the force between two objects. Eventually the Blade of Darkness was stolen by a rogue Jedi and, after the Prime Jedi's passing, the Blade of Light was wielded by the grandmaster of the Jedi Order for many centuries on as a tradition to honour the contributions the Prime Jedi made to the order. The Blade of Light would later be destroyed by a dark warrior in 8600 BBY. Around the same time, the Blade of Darkness was lost by the descendants of the dark warrior who first stole it.