This blue-bladed lightsaber was owned by Padawan Cal Kestis when he was apprenticed to Jedi General Jaro Tapal during the Clone Wars.
Kestis had been practicing his skills in lightsaber combat under his Master's supervision when Order 66 was issued to the clone troopers, forcing the young Jedi to defend himself against his own soldiers. He lost his lightsaber in a turbolift shaft while trying to escape from the 13th Battalion onboard the Venator-class Star Destroyer Albedo Brave.
The weapon was shot out of his hands and fell to the bottom of the turbolift shaft, subsequently being lost for good when the warship was destroyed. However, Tapal gave his damaged lightsaber to Kestis, who escaped to the planet Bracca, before dying of his wounds. Later, the young Jedi created a new lightsaber by combining the one his master gave him and the one from Jedi Knight Cere Junda.