Masters of the Council could access the Sith holocrons in the Jedi archives which was one of the reasons Anakin was upset with the council when they didn't
give him master status in ROTS. He wanted to find the knowledge there to save Padme. It's conceivable that Obi-Wan at some point got his knowledge of
crytals in that way. He had some experience with Sith holocrons prior to WS. He was responsible for finding and bringing a Sith holocron to the Temple on at
least one occasion.




