Korfax at Light's Hope Chapel in the Eastern Plaguelands wants you to bring him 1 Frozen Rune, 1 Blue Sapphire and 1 Arcanite Bar.
Fixing this band may prove to be quite challenging, [player]. You see, it was made from the very runes that form inside Scourge structures - like Naxxramas. Additional materials are also required but your main concern should be getting those frozen runes. Bring me what I need and I will restore the ring to its former glory.