Flames commonly burn with a yellow and orange color scheme, but the hues are not usually clearly defined or vivid. If you want to create an interesting display when lighting your candles, you can create colored wicks that will allow your candles to burn bright in all the colors of the rainbow. You can use these wicks in the production of simple, homemade, colored-flame candles for use at parties, on cakes or simply to add a nice touch of decoration.
Choose the chemical for the color you want for the flames. Strontium chloride burns red; calcium carbonate burns orange; sodium chloride burns yellow; boric acid burns green; copper chloride burns blue; potassium chloride burns purple; and magnesium sulfate burns white.
Fill a small bowl with your chosen chemical, and soak the candle wicks in the bowl. The wicks don't need to be dripping wet, but the chemicals must be thoroughly soaked into the entire length.
Thread the soaked wicks into the candle mold and plug the open holes at the bottom with clay. The clay will keep the melted wax from coming out of the bottom of the mold.
Fit the double boiler with a candy thermometer and pour the paraffin wax into the top of the boiler. Heat the wax until it reaches 130 degrees Fahrenheit.
Pour the melted wax into the mold around the wicks and let the mold rest for 12 hours at room temperature. Move the mold to the refrigerator for another 12 hours before unmolding.
You can use the same color wax as the color the wick will burn to keep track of your colored candles.
Do not leave burning candles unattended.