A Great and Terrible Beauty by Libba Bray
This YA novel is, in general, unlike most YA novels...it's longer, darker, and written in the Victorian era.
Gemma Doyle moves from India to London to attend finishing school after a terrible tragedy befalls her family. She makes friends, enemies, and discovers she possesses a power unlike anything she has ever known. This novel chronicles her struggles with school, her identity and her ever-increasing power.
Dark and haunting, this is a refreshing change from the "typical" YA novel...
I'm guessing that you know the sequel just came out. ;)