Bone carving was used in the casket now on display in what institution?
Bone carving:  The Anglo-Saxon Franks Casket is a bone casket imitating earlier ivory ones. Franks Casket: The Franks Casket (or the Auzon Casket) is a small Anglo-Saxon whale's bone (not "whalebone" in the sense of baleen) chest from the early 8th century, now in the British Museum.
British Museum