The Shinning Ones (The Tamuli #2)

Book Two of The Tamuli. 

Years ago, the Child-Goddess Aphrael had hidden Bhelliom, the Stone of Power, at the bottom of the sea. Yet now it is needed again to stop a malign force from spreading evil and destruction across the lands. Sparhawk, Queen's champion, sets out to retrieve the Stone. But others seek the gem for their own diabolical ends. Most fearsome of these are the Shining Ones, whose mere touch melts human flesh from bone. Now Sparhawk finds himself stalked by these creatures out of myth . . . whose touch is all too real.