From Start to Finish, Fireworks are a Complex Thing

Today is July 4th, otherwise known as Independence Day in the United States, which means good friends, good food on the grill, good beer, and of course fireworks! On the topic of fireworks and all the wonderful pyrotechnics that will ignite the skies tonight, have you ever wondered how they're made?

It's a little more involved than packing black powder into a cardboard container and calling it good. Actually, it's pretty complex from start to finish. Popular Mechanics took a detailed look at the engineering of fireworks, which start off as handcrafted shells encased in treated cardboard and heavy paper. Inside is a mixture of fuel, an oxygen producer, a binding resin, and color-producing agents designed to light up the sky and dazzle crowds.

In addition to the bursting charge, there are around two and a half dozen other ingredients that work together to propel the firework into the air from tubes on the ground, blow it up, and shoot out various shapes and designs in an array of colors, depending on the desired effect.

"Every pyrotechnic company has a unique approach to pinpointing a desired color, from the intense oranges and reds at one end of the spectrum to the rich violets and blues at the other. But the secret to vibrant colors lies in the stars' chemical makeup," Popular Mechanics explains. "Each color has a distinct recipe, which specifies the precise chemical concentrations of the compounds that should be mixed, as well as sophisticated techniques for grinding, mixing and sculpting these compounds into stars."

A blue violet eruption, for example, will contain (in order of highest to lowest density) potassium perchlorate (KCIO4), polyvinyl chloride, strontium carbonate (SrCO3), copper oxide (CuO), and red gum.

Something neat to keep in mind when you're viewing fireworks later this evening. And on that note, we'd like to wish our readers a happy and safe Fourth of July!