Nearly everyone buying sparklers gravitates towards coloured sparklers as they sound better. In fact, it’s gold sparklers that give off the best sparks and create a more traditional effect. Gold sparklers also give off the least amount of smoke.
Coloured sparklers on the other hand usually burn with a bright coloured flame and emit a lot of smoke. For whatever restrictions of chemistry, it doesn’t seem possible to create the amount of sparks that gold sparklers produce but in a colour such as green, red or blue.
The two photos below, at the same scale, show the differences between a gold sparkler and a coloured one.