This thing is pretty damn cool. lots and lots of mats though.
Alchemist's Stone

You need Revered with "The Sha'tar" for the recipe.

and the mats are:

3x Deep Peridot
3x Shadow Draenite
3x Golden Draenite
3x Blood Garnet
3x Flame Spessarite
3x Azure Moonstone
2x Fel Lotus
7x Primal Earth
7x Primal Water
7x Primal Air
7x Primal Fire
5x Primal Mana

216 hours worth of cooldowns = 9 days.

Gotta love wowhead. http://www.wowhead.com/?item=13503

I have been debating making one of those... just haven't gotten around to it yet!

Nice that it also takes the place of the Philosopher's Stone for other transmutes... that'll free up a bag slot for folks who actually use it for its trinket buffs.