FROZEN chest

I am in Talor's Chute, northeast of Droknar Forge (the area after Dragon's Lair, which is after Ascension). In it are "Frozen Chest" thingies, that I'm assuming are regular chests that are locked. any idea how to open them?

I'll close this once someone suggests a working answer.

i once found a key, which dropped from a ice golem. it was called "Dwarfen Key", and one can apply it to locked chests. however, i got the answer that my key did not fit the lock. so no idea how often one finds key, and how to figure out which key fits into which lock. but please tell me what is in the locked chests once you manage to open one.