The emerald lantern is a lightsource which provides slightly brighter light than sapphire and conventional bullseye lanterns. It’s used during the Lunar Diplomacy quest. It is created by using the emerald lens with a bullseye lantern (unf). It requires lamp oil to be put in it first in order to be lit. It must be lit with a tinderbox. Level 49 Firemaking is required to light it. It is similar to the sapphire lantern, but unlike the sapphire lantern it is not made using a cut gem. If lost, the emerald lens can be recovered by speaking to the Cabin boy who can be found slightly north-west of the Lunar Isle bank.