important relic of the true cross. >> what's fascinating is that it is said to have been given directly by the pope to the king of ireland and rome as we know had access to relics from jerusalem. >> archaeologist georges kazan is joined by scientist tom higham. he is also from oxford university in england, and he will put the relic to the test. >> for the first time in history, we're able to place these relics in their proper time and proper date. >> the waterford cross is on loan to the medieval museum from the roman catholic archdiocese. and museum curator eamon has their permission to test it. >> and the relic is just inside this? >> it's just inside this. >> is that a modern script or an ancient script? >> no, it's a 12th century script. it says a piece of the wood of