I just hit 300 in JC yesterday and i was surprise to see the JC recipe i just learned never pass by orange. These recipes need 300 to learn but they are allready yellow at 300 someone know why?
Starting at 300 you can actually start cutting green gems. I think the green gem cutting can get you up to near 340, where you have to make a ring or two. At 350 you can cut rare gems, but that can get expensive to use as a skillup, so I would continue to use jewelry to skill up. Start checking the AH frequently for cheap designs that you can use to skill up with.