Yes WLK's jewelry formula is a headache. You need to make a daily coin to get Dalaran jewelry, and then buy the formula. The location is NPC's jewelry store in Dalaran. There is another LZ to remember, that is, go to the jewelry processing trainer in the Warsong Fortress to receive a task, and you can get perfect jewelry processing skills after completion. I can't remember the specific name. That's what it means anyway. After you have this skill, you will have a certain chance to cut out a perfect gem when cutting gems, and the attributes are better than ordinary ones.