yes, alchemy can be very profitable depending on how much gems go on your server, and if you have the discipline to x-mute everyday.
usually the most expensive uncut gem is the red one (cardinal ruby)... you will need to buy a scarlet ruby (around 50g on most servers) and go farm some eternal fires (I usually farm a stack, then when its about to end I farm annother stack). say your x-mute don't proc, you will still transform 50g into 160-250 gold. now there are chances it will proc and you can actually turn 50g into 1k gold.
I usually make cardinal rubies every day, and after reset I cut (you can ask a friend to cut if u dont have JC) them into different gems and put them in the AH, you won't sell all of them, but some you will (this morning I had 1.7k gold in mailbox and it was a slow night...)still gems will be accumulating, and so will the gold in your bags