The guide
Making a candle last longer with a warmer lamp
A cut-metal shade casts patterns as well as heat — here is how to set the dragonfly lamp.
Why it lasts longer
A lit wick burns off wax and fragrance together, usually until the jar is hollow in the middle. A warmer only softens the top layer, so the scent is released slowly and the wax is hardly consumed.
How to stretch a jar further
Use the lowest heat that gives you a clear pool. The brightness control is there for exactly this. Use the timer (2, 4 or 8 hours) so a session never outlasts your attention.
When the fragrance fades
After many sessions the oils thin out. At that point scoop the wax out, add a fresh melt or two to the dish, and carry on — nothing goes to waste.