You can see leveling recipe of ascended ring in the latest patch of GW2. One player said that, with the materials of forging cloak, you can level up your ring.
That needs three kinds of materials dropping in Fotm, requiring 5 vials, 3 pieces of gold and 1 shard.
Pay attention, the materials can be both forged the cloak and leveled up your ring. Use them carefully.
ArenaNet said in the patch of yesterday, vial would never drop below level 10. But there is one player farming one vial in game.