Another thing (as you already have received some VERY good advice), the harder the wax the harsher the burn. I see many mention color and scent but honestly you can also tell by touch. If you can make an indention or a fingerprint in the candle before you light it (as in the tall glass "religious candles) it is not going to be nearly as hot as one that is harder. Do NOT under ANY circumstances use sealing wax. It WILL burn and leave a permanent scar.