“How about a little teaser from CROWN OF ICE?

Thyra Winther, the current Snow Queen speaks about her "home":

At night the palace’s crystal halls are tinged sapphire. One of the first bits of magic that Voss taught me was to set the carved walls alight so that I’m not forced to walk the halls in darkness. I conjure a cold light that glows within the thick walls without melting the ice. I mastered this trick quickly once I knew what those shadows held. If I leave an area in darkness, they come—the girls who reigned as Snow Queen before me.
“I must find it.” Their hollow words wind about me like a shroud. “The last piece. I must place it. Give it to me.”