How to Make Colored Fire at Home

It’s easy to make colored fire at home in the fireplace or a campfire. All you need to do is add certain metal salts to the fire to produce brightly colored flames. Here is a list of common flame colorants, the colors they produce, where to find them, and how to use them safely.

List of Flame Colorant Chemicals

Many chemicals produce colors in a fire, but not all of them are readily available or safe to use. This is a list of common colorant chemicals and the fire colors they produced.

*Copper chloride results in a blue to blue-green flame. Producing a pure blue flame is difficult because copper compounds often emit both blue and green wavelengths. Most “blue fire” demonstrations appear blue-green rather than deep blue.

The colors are based on the flame test in chemistry, which uses a blue alcohol or gas flame. When these chemicals are added to a wood fire, a rainbow effect is more likely due to the chemical composition of the fuel.

How to Color Fire

Once you have the colorant chemicals, there are different ways to use them:

• Sprinkle dry colorants onto flames.
• Dissolve the colorants in alcohol and then soak logs in the liquid.
• Dissolve the colorants in water. Soak pinecones, rolled newspapers, sawdust, or cork in the liquid. Allow the fuel to dry and then add it to a fire for a pop of color.

There is no “recipe” for how much colorant to add to water or alcohol. The amount that dissolves depends on the temperature of the liquid and the solubility of the chemical. Basically, just add as much solid as will dissolve in the liquid. If you use less, the color of the fire may not be as intense. If you use too much, you’ll have undissolved solid, which you can recover and use later. Some compounds dissolve better in water, while some dissolve better in alcohol. Test a small amount and decide which method works best for your needs.

Do not mix all the colorants together. You won’t get a rainbow! Most likely, you’ll end up with a yellow fire. This is because sodium (in table salt and also naturally in wood) overwhelms other colors. For a multicolored fire, it’s best to add several pine cones, each treated with one colorant, or a mix of dried colored sawdust. Even with separate colorants, it’s best to avoid adding “yellow” because it’s so bright. For the most vivid results, use clean fuel and high-purity colorants.

Why Do These Chemicals Change Flame Colors?

When a metal salt is heated in a flame, its electrons absorb energy and move to higher energy levels. As the electrons return to lower energy states, they release light of specific wavelengths. Because each element has a unique electronic structure, it produces characteristic flame colors.

This same principle is used in chemistry flame tests to identify unknown metal ions.

Where to Find Flame Colorants

Most of the flame colorants listed here are available at grocery stores or home supply stores. A few are easier to find online. Some of these chemicals are available either as solids or as liquids. Liquids are fine to use for soaking pinecones or logs, but obviously aren’t a great choice for applying directly to a fire (unless you want to put it out).

Best Colorants for Each Flame Color

Not all flame colorants perform equally well in a campfire. Some colors are easier to produce than others.

For beginners, green flames from boric acid and red flames from strontium chloride are the most reliable and vivid.

Other Ways to Make Colored Fire

Directly adding salts to a fire is the best way to color fire, but it isn’t the only method. Colored flames also result from burning color-print newspaper, magazines, and some plastics, like garden hoses. While these other methods produce colored fire, their combustion may also release toxic fumes. Color-printed paper is reasonably safe to burn, although it may release cinders that can ignite nearby objects. Burning plastic is never a good idea because the smoke contains toxic and potentially carcinogenic chemicals.

Black Flames

Making black flames is possible, too. However, this color works a bit differently because you absorb the colored light from the fire, leaving darkness.

Why Doesn’t My Colored Fire Change Color?

Several factors reduce or eliminate flame colors:

• Too much sodium contamination from salt, ash, or impurities.
• Wet wood produces steam that masks colors.
• Low fire temperature.
• Using too little colorant.
• Adding chemicals all at once instead of separately.
• Wind dispersing the color-producing vapors.
• Using treated or painted wood.

For best results, start with a hot fire, use dry fuel, and add one colorant at a time.

Can You Cook or Roast Marshmallows Over Colored Flames?

It is best not to cook food directly over colored flames.

Many flame colorants are common household chemicals, but some contain metals that are not intended for consumption. Small amounts may deposit on food through smoke, ash, or soot. If you plan to cook over a campfire, wait until the colored fuel has completely burned and use fresh coals for cooking.

Safety Information

Colored fire is safe in a fireplace or campfire, but it’s probably not wise to cook hotdogs or roast marshmallows over colored flames. For the most part, using salts produces the same smoke as a normal fire. The salts don’t actually burn in the flames, so they remain in the soot rather than in gases around the fire. For this reason, take care where you dispose of ashes. Using Epsom salts may actually help your garden. Plants also appreciate a boost of boron from borax or boric acid, but too much is harmful. Copper salts naturally occur in soil, but copper is toxic to invertebrates like snails and crabs and other organisms, like algae.

Like other home chemicals, flame colorants should be kept out of reach of children and pets. Read and adhere to any warnings on chemical containers.

If you use alcohol as a fuel, please remember that it is much more flammable than wood. Never add alcohol (or any liquid fuel) to a burning fire, or it will react much light lighter fluid!

Commercial Colored Fire Packets

If you do not want to handle individual chemicals, commercially prepared fire-color packets are available. Simply place an unopened packet into a campfire, fire pit, or fireplace. The packet burns and releases color-producing compounds over time.

Advantages include:

• No measuring or mixing
• Cleaner handling
• Longer-lasting color effects
• Better color variety

These products are often sold as “fire color packets,” “magic fire,” or “rainbow fire” packets.

FAQs

What chemical makes fire green?

Boric acid and copper sulfate are among the easiest chemicals to use for producing green flames.

What chemical makes fire blue?

Copper chloride produces blue to blue-green flames. Achieving a deep pure blue flame is difficult because traces of other elements often alter the color.

Can table salt make blue fire?

No. Table salt contains sodium, which produces a bright yellow flame.

Why is my colored fire yellow?

Sodium contamination is usually responsible. Even tiny amounts of sodium can overwhelm other flame colors.

Are colored fire packets safe?

Commercial fire-color packets are generally safer and more convenient than handling individual chemicals because the ingredients are pre-measured and packaged.

References

• Barrow, R. F.; Caldin, E. F. (1949). “Some Spectroscopic Observations on Pyrotechnic Flames”. Proceedings of the Physical Society. Section B. 62 (1): 32–39. doi:10.1088/0370-1301/62/1/305
• Natural Resources Canada (2003). Pyrotechnics Special Effects Manual (2nd ed.). Minister of Public Works and Government Services Canada.
• Patnaik, Pradyot (2002). Handbook of Inorganic Chemicals. McGraw-Hill. ISBN 0-07-049439-8