However, while soy candles are great to burn in your home, there are some negatives to using soy wax.  Soy wax can be sensitive to changing temperatures and exhibit small crystals in the wax called "frosting".  This should not be considered a flaw since the candle will burn and smell fine.  It is also an indication that the candle is made without using paraffin additives which help to combat frosting. These small crystals are more obvious in a dyed candle so select undyed if this is a concern.