In essence, a lightsaber’s color reveals something about its wielder and their personality. Lucasfilm’s Pablo Hidalgo has explained that the Kyber crystals used to make lightsabers start out colorless. The crystals only take on a color once they have been gathered and a bond between the crystal and the saber’s user has been formed during the creation of the weapon. There’s even been an instance in which a yellow saber was made from unstable red saber crystal, when Jedi Jaden Korr purified it and the crystal turned yellow, granting him his third lightsaber.
Just like the blue and green lightsabers, the yellow lightsaber is associated with an important school of thought within the Jedi Order: that of the Sentinels (via Ubersabers). Star Wars lore explains that the Sentinels seek a balance between the Consulars and the Guardians, and also wish to educate themselves on other more practical aspects of life such as tracking techniques and espionage. Unlike some others in the Jedi Order, Sentinels recognize that the Force isn’t actually the solution to everything.
The yellow lightsaber is most commonly seen in the Jedi Temple Guards’ pikes on the Star Wars animated series The Clone Wars. The Temple Guards wield double-bladed yellow sabers, much like the dual-ended red weapon Darth Maul hefted before it was sliced in half. These lightsabers don’t personally belong to the Temple Guards, but are instead the property of the position they hold.
Additionally, there are other past sightings of yellow lightsabers — including in the hands of bounty hunter Asajj Ventress, who apparently found her lightsaber on the black market (anyone else getting maybe-she-killed-a-Jedi-and-stole-it vibes?). Ventress’ blade was identical to those of the Jedi, rather than the more blade-like appearance of the pikes wielded by the Temple Guard. Another Star Wars character said to have carried a yellow lightsaber is Anakin Skywalker’s Padawan learner Ahsoka Tano. Though George Lucas nixed the idea of Ahsoka using a full-on yellow saber on Star Wars: The Clone Wars, Ahsoka’s mostly green saber was altered to give off a slightly yellow glow.
Read More: https://www.looper.com/173922/what-the-yellow-lightsaber-in-star-wars-means/?utm_campaign=clip