WHAT DO LIGHTSABERS' COLOURS MEAN?
STUDENT´S WRITING
In the first six episodes of Star Wars films lightsabers were red, blue and green; and purple only for Mace Windu because the actor asked for it. On the contrary, in the Expanded Universe there were many different colours. Although now colours are used for decoration, in the past they could have had a meaning.
In the original trilogy, the jedis' lightsabers were blue but the Sith´s were red. This could be a simple code, blue for the good ones and red for bad ones. 
Despite Jedis´ lightsabers were blue, Yoda´s and Qui-Gon´s were green and also Luke Skywalker´s was green in episode VI The Return of the Jedi. This was because George Lucas thought that Luke´s lightsaber couldn't be seen clearly in the battle versus Jabba el Hutt over the Sarlacc.
On the other hand, the Imperial ships' lasers were green but the Rebellion ships' lasers were red. So we can´t say that colors are an actual code for the good ones and the bad ones.
Actually, the lightsabers´ colour depends on the crystal used to concentrate energy when the lightsaber is built. After the Old Republic, the Lord Siths´ lightsabers used to be red because there were made with artificial crystals.
On the other hand, the Jedis´ lightsabers used to be green or blue because they were made with Adegan natural crystal form Ilum planet. Padawans performed a ceremony in the ice caverns form this planet, where they found these natural crystals.
Finally, we can say that there are many different colours for lightsabers (there was even a black one once) but there is not a simple clear code for them. It depends on the historical moment in the story, the contrast with the setting, directors´ decisions or even actors´choices.
On the other hand, the Jedis´ lightsabers used to be green or blue because they were made with Adegan natural crystal form Ilum planet. Padawans performed a ceremony in the ice caverns form this planet, where they found these natural crystals.Finally, we can say that there are many different colours for lightsabers (there was even a black one once) but there is not a simple clear code for them. It depends on the historical moment in the story, the contrast with the setting, directors´ decisions or even actors´choices.
by Alex Leal
