How to Arrange the Stars in Fireworks?

Colours come from the different kinds of metal inside the sparkler. They have to be elements that can accept heat and not participate in the reaction. If you're the person designing these fireworks, you think it's almost like your painting with materials. And a lot of these things are made sort of by hand, like they areThese works masters that pack these things together and very carefully mix the ingredients. You know how black powder goes off, it then sets off the sparklers, which then glow? It must take a lot of experimentation exactly how to ange those stars inside the firework to give you that reaction. Ty've done someike really complicated computer stimulations to figure out exactly