There are 5 jedi lightsaber christals and here are the locations:

red crystal: on the rouge shadow

blue crytsal: on rixus prime(2)& the fungas planet

green crystal: rixus prime(2) & the planet with wookies(2)

Purple crystal: fungas planet(2)

yellow crystal: rixus prime

P.S. you keep them all of the game!!!!!!!!!!!!!!