with the german lord henry the lion. we know that he visited constantinople and requested relics. but it's possible that may have had origins much older than that. ♪ >> should we get the bone out and we'll look at it now? >> sitting in an elaborate gilt housing dating back to the 14th century, for the researchers, the challenge will be how to remove the bone from its precious casing. ♪ and when they try to extract the bone from its mount, there's a problem. >> the mount does not come off of the bone. >> oh, you mean i can't actually take the bone out? >> no. >> and that means tom will struggle to reach the central part of the finger containing collagen, the most reliable