Rare/Unique/Powerful Skill gems?

"

agememnon13 wrote:

Wouldn't another idea maybe be to make *multicolored* gems? so multiple archetypes can use each gem? Like...

Blue+red=purple gem, so it could be formulated for templars, but also a witch or a marauder could use it. I'm not sure what the ability could be. But gem and character customization could REALLY open up if we tried mixing...