Updated For 5.4 Mists of Pandaria

Gem Quality

Color Popularity Gem Quality Auction Price
Yellow/Blue 6 star Radiant Chrysoprase
+5 Critical Strike and +5 PvP Power
Epic
Red/Yellow/Blue 6 star Nightmare Tear
+10 All Stats
Epic
Red/Yellow/Blue 3 star Void Sphere
+4 Resist All
Epic