Blue Color Crystal

The Blue Color Crystal can be crafted by players who have taken the Artifice crew skill and reach Artifice Level 1. This crystal can also be bought on the GTN from other players. The schematic to craft it will become automatically available at the Artifice Crew Skill trainer once you reach Artifice Level 1. Artifice Guide

These versions of the Blue crystal are available:

• Advanced Blue Indestructible Crystal +41 Endurance
• Advanced Blue Hawkeye Crystal +41 Power
• Advanced Blue Eviscerating Crystal +41 Crit
• Advanced Blue War Hero Crystal +41 Mastery (The mastery version can also be bought from the PvP vendor on the fleet, but it costs 200000 credits and require Valor 10. The crafted version does not have a Valor requirement.)

Blue Crystal Lore

Traditionally, in Old Republic lore, the blue lightsaber crystal was used by Jedi Guardians. "This Jedi battles against the forces of evil and the Dark Side. They Focus more on combat training and the use of the lightsaber." However, in Old Republic lore, it is not uncommon to find Fallen Jedi wielding their crystals earned during their time with the Jedi. Notable Old Republic blue lightsaber wielders include Satele Shan and the Fallen Jedi Exar Kun. In movie lore, notable blue lightsaber wielders include Obi-Wan Kenobi and the the lightsaber passed down to Luke Skywalker in "A New Hope".