"The crystal is the heart of the blade. The heart is the crystal of the Jedi. The Jedi is the crystal of the Force. The Force is the blade of the heart. All are intertwined: the crystal, the blade, the Jedi. You are one."- Luminara Unduli, during Barriss Offee's lightsaber construction ceremony on Ilum.
Adegan crystals: The Force shared a special connection with Adegan crystals and it was through their use that Jedi created a bond amongst themselves, the Force, and their weapon. This trait caused the Adegan crystals in a lightsaber to give off a weak Force signature that could be sensed by any Jedi.
The methite and pontite variants of Adegan crystals, which produced the best lightsaber blades, were similar in structure to Ilum crystals. This caused some to use their names synonymously, though crystals from Ilum were much more common. Ilum presented to the Jedi Order entire caves full of high-quality crystals, while Adegan crystals were even rare in their own system. This led to Ilum crystals being the most commonly used lightsaber crystals amongst the Jedi up until the Great Jedi Purge. Most Jedi Padawans underwent the ritual on construction of their first lightsaber at Ilum.
The vast majority of lightsaber crystals from Ilum were green or blue in color and, though they were not connected to the Force like the Adegan crystals were, all of them had the special properties that made them ideal for a Jedi's weapon.
Kaiburr crystal : The Kaiburr crystal was an ancient Force relic, initially located on the planet Circarpous V, locally known as Mimban. When in its natural location in the Temple of Pomojema on Mimban, the crystal increased a Force-sensitive's power one thousand times over. Among its magnification of abilities were the ability to heal, to further augment a Force-user's connection to the Force, to project Force lightning by those typically unable, and to empower and energize a tired being close in proximity to the crystal. If cut properly, the Kaiburr crystal also worked as a lightsaber crystal.
The Kaiburr crystal was initially used by priests to heal the sick in the Temple of Pomojema. However, for reasons unknown, the area was abandoned, and the crystal became a legend in the eyes of the local Mimbanites. The crystal would go on as a legend until around 2 ABY, when an elder woman named Halla purchased from one of the Mimbanites a shard of the crystal, as well as a map which led to Pomojema's temple. The woman enlisted the help of Luke Skywalker and Leia Organa, on Mimban due to a crash-landing, and helped the two escape from prison. Unknown to the three of them, this caught the attention of the Dark Lord of the Sith Darth Vader; unaware, she and her allies went on an expedition to acquire the ancient relic.
formed crystal colors.
Blue: mostly used by jedi Guardians or people who focused on lightsaber combat and sometimes by darkside adapts.
most notable users are: Anakin Skywalker, Obi-Wan Kenobi.
Green: mostly used by the Jedi who focused on the force like Consular.
most notable users are : Nomi Sunrider, Vima Sunrider, Yoda, Shaak Ti, and Kit Fisto.
Purple: was mostly used by people who walked a very fine line between light and dark or has fallen and came back and use it as a reminder of what happend.
most notable users are: Mara Jade, Mace windu and Revan.
Yellow: where mostly used by jedi like the Sentinels who walked the middle path between Guardians and Consular.
most notable users are : Bastilla Shan and Micah Giiett and every other jedi Sentinel.
Red: red none synth crystals are so rare the there is only on recorded use which was Daarth Vader.
"I don't need to remind you that a crimson blade doesn't guarantee that the wielder is a Sith, any more than every person strong in the Force is a Jedi. Asajj Ventress was a mere apprentice to Dooku, not a true Sith. A crimson blade can owe to nothing more than a synthetic power crystal. Then crimson is simply a color, like Master Windu's amethyst blade."
A Synthetic lightsaber crystal, commonly referred to as a Synth-crystal, is a type of lightsaber crystal that is artificially created, rather than naturally formed by geological processes. Due to the methods used in their creation, they often formed with a red coloration, though they could be made with any color through special manipulations of either the creation process or the crystal itself, often through the Force, such as the green synth-crystal powering Luke Skywalker's second lightsaber. since The Empire Banned and punished people with death if found with a lightsaber crystal most on the run jedi could not get to the normal places they would go to for crystals so they had to make their own.
Red: Red synth Crystals was mostly used by sith of any time period and even a few jedi like Adi Gallia.
known users: most sith and Adi Gallia.
Green: mostly used by lukes Jedi Praxeum in the early stages they did not know where to find crystals since palpatine had destoryed most crystal caves on places like Illum.
Blue: mostly used by lukes Jedi Praxeum in the early stages they did not know where to find crystals since palpatine had destoryed most crystal caves on places like Illum.
Purple: only used by one known user Jaina Solo since she want something made only for her and other lightsaber crystals did not seem right so she made her own.
Silver/white: mostly used by force users who are not part of the sith and jedi orders such as the Imperial Knights during the Fel Empire named after its founder Jagged Fel and husband to Jaina Solo who May have Trained the First Generation of the Imperial Knights.
one of a kind crystals
Bane`s Heart: a red synth crystal made by Darth Zannah who was the only one who could use it.
Meetra Surik crystal: was a naturally-formed crystal that had forged a bond with the Jedi Meetra Surik, resonating with her and her relationship with the Force. As a result, the crystal acquired its character from Surik and had the ability to augment her powers.
Shaela Nuur's Solari crystal: was one of the oldest and most powerful lightsaber crystals of the Jedi Order. It was a light orange gem that only a Jedi who was pure in spirit and an ardent follower of the light side of the Force could use.