I am currently on the second portion of the Relics of the Golden Age quest and when talking to Tyra Karn I am able to simply accept an infinite number of Drangs which I can then dismantle. It should dismantle into nothing if it is going to be repeatedly retrievable. I have a screenshot but am posting from my phone Thanks to Crytikalmass below turns out I just wasn't paying attention. It costs 10 legendary shards to but one.