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No, your candle is not drying out. Frosting is a natural characteristic of soy, and is part of the soy experience! It is not a flaw, and it is strictly unique to pure soy candles. Often times it is called the "bloom." Actually, many customers are concerned if there is not frosting on their soy candles. It is a way that a customer can tell if their candle is really made with pure, all-natural soy wax. Frosting does not effect the scent throw or the burning properties of the candle. You can safely burn a candle with a bloom without worry. Frosting is a particular crystal growth of vegetable oils. It will cause the candle to look dry, which is simply a characteristic of that crystal structure, but has nothing to do with the candle "drying out".
To minimize frosting, try to keep your candle out of direct sunlight and fluorescent lighting. Even changes in the weather can cause additional frosting. It is almost impossible to stop the soy wax from blooming. It's just one of the beautiful and natural features of this wonderful wax