Sea glass

the long version

"Student glass magician Opal Cowan's newfound ability to steal a magician's powers makes her too powerful. Ordered to house arrest by the Council, Opal dares defy them, traveling to the Moon Clan's lands in search of Ulrick, the man she thinks she loves. Thinks, because another man--now her prisoner--claims Ulrick's desire for blood magic has eclipsed his passion for her. In hostile territory, without proof or allies, Opal isn't sure whom to trust. She can't forget Kade, the handsome Stormdancer who doesn't want to let her get close. And now everyone else is after Opal's special powers for their own deadly gain..."--p.[4] of cover.