Lamp of Long Burning
by Andrew TheisenType: Wondrous Item
Source: RC 240
This item appears to be a standard hooded lantern (PHB, p. 126). When filled with oil and lighted, it will burn continuously without need of further oil. If the flame is ever doused with water, the lamp becomes non-magical.
Faint evocation; CL 1st; Craft Wondrous Item, light; price 800 gp; Weight 2 lb.