Storm Glass by Maria V Snyder

Untrained. Untested. Unleashed. With her unique magical abilities, Opal has always felt unsure of her place at Sitia's magic academy. But when the Stormdancer clan needs help, Opal's knowledge makes her the perfect choice - until the mission goes awry. Pulling her powers in unfamiliar directions, Opal finds herself tapping into a new kind of magic as stunningly potent as it is frightening. Now Opal must deal with plotters out to destroy the Stormdancer clan, as well as a traitor in their midst. With danger and deception rising around her, will Opal's untested abilities destroy her - or save them all?

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