You have a number of options when it's time to add color to your homemade candles. Crayons are one option that often comes to mind, but will they actually work?
It's a common question and the simple answer is that you can use crayons to give wax candles color. However, the results are not perfect, or even ideal, in the candle-making world. The good news is that there are inexpensive and readily available options that will create better candles.
Crayons Will Work, But...
Crayons can be used to add color to your candles, though it's not your best option. If you want to make the best homemade candles possible, we're going to recommend that you skip the crayons. There's a very simple reason why.
Like paint, crayons are colored with pigments. Pigments appear to change an object or substance's color by reflecting or absorbing different wavelengths of light. However, the pigments don't dissolve in wax, they're just dispersed and basically left floating around. This may not seem like a problem at first, but when you light the candle, you will notice the difference.
As the wax melts and is carried through the wick to the flame, the pigments will clog the wick. Think of it like dirty deposits in your gasoline that clog up your fuel line. That's what happens with pigments. The pigments that don't clog the wick tend to settle and/or concentrate at the bottom of the melted wax.
Dyes Are Best
The best solution for coloring wax is a dye. The dye actually dissolves into the wax and won't clog the wick, which is why dyes are the preferred colorant for making candles.
There are a number of dyes available that are specifically made for candle wax. They come in liquid and "chip" form and are really inexpensive. These will produce the best results.
While candle dyes are your best option, they are not the only one. There are a couple of other ways to add color to your candles and they will yield better results than crayons.
A Natural Alternative
A fun option, particularly if you're interested in making all-natural candles, is to infuse the wax with natural colors. Herbs like comfrey, lavender, and rose hips can be used to add interesting colors to your wax. These work because the color is actually dissolved in the wax, just like a dye.
Some of the colors, like spirulina or peppermint, would likely turn out darker if the herbs are ground into a powder and simply dispersed into the candle wax. However, that method would probably act more like a pigment and either clog the wick or settle to the bottom, or both.