does anyone know anything about aromatherapy?

[feawen]

I need fellow mooters help!

Its my boyfriends birthday coming up soon and i didnt just want to go out and buy something meaningless. Two days after his birthday im leaving to go traveling around new zealand so we will be apart for two months and i want to leave him something to remember me by.

So to cut a long story short this is my idea...

My boyfriend is going thought a very bad patch at the moment. His working all hours, hates his job and is very stressed and tired. His is also very into making candles, and he has left his candle making set at my house. I know i could just buy him some relaxing candles but i wanted to personalise it a bit.
So i was wondering if any of you know anything about aromatherapy and if there was any oils which would promote relaxation, calm and sleep?

Ok essay over! thanks for reading it!