By Blizzard making red the primary gem for almost every PvE build and THEN making it no better drop rate than other colors.... bottleneck = profit.

Think about profs. We upgrade gear so often in this game, gems and enchants are always going to be the big profs. Enchants aren't as high in my book because everyone gets enchant mats from group DE or vendors. You can't buy Gem's this expansion except in DS raid. Also, some enchant slots are different profs like LW and Tailors for legs. Only JC's can do gem slots... no competition for those slots. Hands down... JC.

Others can make money... but JC wins.

For serious, jc... I just recently started trying to make money out of jc, and with a little bit of effort over three weeks or so, I'm probably going to hit the 100k mark in the next couple of days.

While it's the process of prospecting ore and cutting gems that's making me heaps of money, it's definitely supported by alchemy (i mail carnelians, alicites and zephyrites to my xmute master alt to change to blue gems, which I then craft into cut inferno rubies and the amberjewel and ocean sapphire pvp gear) and by enchanting, to de jc gear made from hessonites and jasper, and to turn that into profitable enchants. It's really a three profession synergy that makes me money.

Separately, i make a fair bit of cash from my tailoring/inscription alt, who turns chaos orbs into dreamcloth, and then into spellthread, and makes mysterious fortune cards whenever herbs get cheap.