How are fireworks made?

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Five Guys Facts

7 min readJan 9, 2017

Fireworks are dope — making them is just as dope. Here’s how you do it:

The History

Gunpowder is a mixture of sulfur, charcoal, and potassium nitrate. The sulfur and charcoal work as fuel, while the potassium nitrate (also known as saltpeter) acts as an oxidizer.

The Chinese were the first to discover the explosive properties of this chemical mixture somewhere between the 600s and 800s. The first record of fireworks is from a Taoist monk named Zhenyuan miaodao yaolüe in the 1800s:“Some have heated together sulfur, realgar and saltpeter with honey; smoke and flames result, so that their hands and faces have been burnt, and even the whole house where they were working burned down.”

The Chinese wasted no time making use of this new discovery, and quickly started manufacturing countless weapons with gunpowder (the Chinese word for which literally means “fire medicine”).

However, the Chinese weren’t all business, and began using gunpowder for entertainment as well. They began creating extravagant explosive pyrotechnics for annual festivals and celebrations, and in doing so started a worldwide tradition of Fireworks. Civilians could buy fireworks from market vendors starting in the late 900s, and numerous world travelers from the 900s to the late 1700s made note of the glorious displays of fireworks found in China. Gunpowder (and fireworks) soon spread to the Arab world and then to Europe and eventually America, and fireworks could eventually be found everywhere.

The Structure

Let’s start small. A firecracker is simply gunpowder that is rolled in some paper and then has a fuse stuck in it. The fuse is lit, and once the lit fuse burns down to the gunpowder, the gunpowder explodes.

How about a sparkler? A sparkler is a stick that is coated in a special type of gunpowder that has two notable characteristics. First, the fuel and oxidizer are proportioned so that it burns slowly, instead of having one giant explosion at once. Second, various flecks of metals like aluminum, iron, and steel are added. These metal dust flecks are what actually create the sparks you see.

Getting a little bit bigger we have fountains. These shoot out small fountains of sparks above them. They work by packing the same type of material you see in the sparkler into a very small, tight tube, which is shaped like a cone. This shape, which professionals call a “choke”, creates a pressure buildup that forces the sparks high up.

Now for the big boys — shells. These are what are used to create most of the big “burst” explosions you see in major firework demonstrations.

A shell needs to two major things. First, it needs to get really high into the sky. Second, it needs to explode into pretty shapes and colors. So, how does it do this?

The shell has two major compartments — a bottom “lift” area, and a top “display” area. The fuse first feeds into the bottom area, which is filled with black powder and is attached to a secondary fuse. When the initial fuse burns down to this “lift” area’s black powder, the bottom compartment explodes, sending the top portion of the shell flying high into the air, and igniting the secondary fuse.

Now, the end of the secondary fuse is attached to another area of black powder. This black powder has little balls called “stars” interspersed throughout it in very particular geometric arrangements. These stars are basically made of gunpowder plus specific chemicals that create pretty colors when burned.

The secondary fuse is designed to burn at a precise rate so that when the primary shell compartment is at the peak of it’s trajectory, based on the explosive power of the “lift” compartment, the secondary fuse will reach the gunpowder in the primary compartment and cause a secondary explosion. This is the explosion that we all notice in the sky.

Now, the reason this explosion looks so good is that the stars I mentioned earlier are laid out in a precise geometric arrangement, creating the geometric bursts you see in the sky. So, for instance, you can see that the above cross-sectioned firework is made of concentric circles of stars. As a result, this creates a 3D sphere effect when the shell explodes. However, countless other patterns are possible, such as smiley faces.

The Colors

As was mentioned, and as you may have learned in high school chemistry, specific chemical compounds create certain colors when burned (and in fact the color that a compound makes in a flame test is precisely the color that compound will make in a firework). Below are some of the main ones used in fireworks:

Strong Red: Strontium Carbide

Weak Red: Lithium

Orange: Calcium

Yellow: Sodium

Green: Barium

Blue: Copper Halides (this is the hardest color to make in Fireworks)

Indigo: Cesium

Violet: Potassium or Rubidium

Gold: Charcoal or Iron

White: Titanium or Aluminum

More Complex Patterns

While I described the most basic shell above, fireworks can get a LOT more complicated. Below are some of the cool effects that exist out there:

The Dahlia

Made like a regular shell, but with fewer yet larger stars. Such stars travel much further before burning out, creating the nice tails you see here

Multi Break Shells

You can add more compartments to a firework shell, each of which shoots off the previous explosion and explodes after another delay. This can create very cool chains of explosions.

The Waterfall

If you fill a shell with just a few stars that are very slow burning and very heavy (so that they don’t go very far, and fall soon after an explosion), you can create very cool “waterfall” effects.

The Farfalle

N0 clue how to make this but it’s dope.

Salute Firework

Some fireworks have a lot of flash powder (powder that explodes in a big dust explosion) instead of stars, causing powerful powdery effects like that shown below. Flash powder is also extremely loud, and so salute fireworks are often used in finales to create huge sounds that complement traditional pyrotechnics.

Here’s a list of a lot of the different effects:

Other Random Fireworks Facts

Making fireworks is really dangerous at a large scale. Any room or building that is filled with black powder of different forms will eventually have black powder particulates dissolved everywhere into the air. As a result, a spark anywhere in such a building will cause the entire place to explode. As you can imagine, this has caused some monumental disasters like this and this and this.

2. Queen Elizabeth was so fascinated with fireworks that she created an honorary title, “Fire Master of England” for the individual who created the best fireworks.

3. At first fireworks were only orange and white due to the chemicals available.

4. The biggest annual fireworks display event in Europe is the International Festival concert held in Edinburgh, Scotland, in which a million fireworks are set off in less than an hour.

5. ~9,000 people are injured by fireworks in America per year. Probably primarily from morons like this.