They are found at the orange and purple amber mines just outside the Kurzick fort. They are a bundle that should be carried to Master Architect Gunther or either of the Kurzick gatekeepers. If brought to the master architect, it will add +2% towards the creation of the Gods' Vengeance superweapon, reducing the time that the Kurzicks need to hold against the attacking Luxons. If brought to one of the gate keepers, they will repair the innermost destroyed gate on his side, resurrecting its guard NPCs.