Fireworks are one of the many traditional characteristics of the Maltese islands. Most love them and are fascinated by the marvellous creations that our various firework factories come up with. Others are not so enthusiastic about the noise… but that is something for some other time to discuss…
Anyhow, I am not a big fan of the loud noises but I must say am truly mesmerised by the colourful spectacles produced. Most might not appreciate the countless hours of work that are involved in creating a few minutes of show… It takes a whole year for pyrotechnic workers to produce all the fireworks for a week of spectacles in one Maltese feast, and that is a lot of dedication, when you come to think that they do it for free! They sacrifice time with family and relaxation to give us people a good show, whilst risking their lives…
The invention of coloured fireworks is relatively recent and not all colours are easy to produce.
Firecrackers were first invented serendipitous by the Chinese in 200 B.C. But it wasn’t until one thousand years later that Chinese alchemists developed fireworks in 800 A.D. These early fireworks were mostly bright and noisy concoctions designed to scare evil spirits — not the colourful, controlled explosions we see today.
Fast forward another millennium and the Italians figured out how to add colour by introducing various elements to the flammable mix. Adding the element strontium to a colour pyrotechnic mix produces a red flame; copper, blue; barium, green; and sodium for yellow.
Even though the chemistry of these colours isn’t new, each generation seems to get excited by the colours splashed across the sky. We now have a wide range of flame colours: red, green, blue, yellow, purple, and variations of these.
Not all colours of fireworks are equally easy to create. Talking to a pyrotechnic expert, it appears that blue is the most difficult colour to produce. That is because the evening sky is a shade of blue, which means that most blues do not show up as well. If you try to make the blue brighter to contrast with the background it can look washed out. The right balance of copper and other chemicals in the flame or combustion reaction produce the best blue colour flame in a firework.
This pyrotechnic worker, has said that to create the best blue flame colour, this needs to be just bright enough to stand out against the night sky but still a rich blue. Another difficulty in creating an intense blue colour is that the chemistry is not simple. It requires a combination of several chemicals and the element copper.
So when you see blue-coloured dots of light creating a pattern in the night sky, you really are seeing excited electrons releasing energy as blue light.