The secret texts, book 2 : Vengeance of dragons
Holly Lisle1999

Kait Galwiegh seeks the Mirror of Souls in order to resurrect her lost family, but in order to get it she must battle with Crispin Abir who believes the artefact will make him into a god. However, using the artefact will unleash the souls of long-dead sorcerers who once conquered the world.