I imagine there must be a firework designer somewhere - 'blue sparks on a background of white flame punctuated by showers of red' he might write and then choose and pack the chemicals accordingly. I imagine them in layers inside the cardboard tube like different coloured sand from the Isle of Wight. Then I think of all the experiments and demonstrations I used to do with my pupils and students - the magnesium burning with the intense white flame and the beautiful green and blue of the burning copper salt. Some colours are easy to get, some are impossible.
Alongside the ground fireworks there are always a good few rockets (a particular passion), and always, my favourite, a Catherine wheel. I came across the origin of the Catherine wheel in a rather excellent novel I have spent the entire day reading - SUMMIT AVENUE by Mary Sharratt. Although today's Catherine wheels are named after the wheel upon which St Catherine was martyred, original Catherine wheels were part of a pagan rite. On the longest day the sun was worshipped by sending burning wheels down a hillsidet into the mill stream below.
We always round things off with sparklers - writing our names in the air.