Anyone know about these lanterns?

[Martin Moser]

I seem to recall watching a TV programme about making sheets of horn like this which probably involved soaking or some such, but there are others more gifted in the craft department than I who could fill you in on that

Details on this can be found in: MacGregor, Arthur. Bone, Antler, Ivory, and Horn: The Technology of Skeletal Materials since the Roman Period. London 1985.