What determines the color and quality of fireworks?

Pure colors require pure ingredients. Even trace amounts of sodium impurities (yellow-orange) are sufficient to overpower or alter other colors. Careful formulation is required so that too much smoke or residue does not mask the color. With fireworks, as with other things, cost often relates to quality. The skill of the manufacturer and the date the firework was produced greatly affect the final display.

Colour	Compound
Red	strontium salts, lithium salts lithium carbonate, Li 2 CO 3 = red strontium carbonate, SrCO 3 = bright red
Red Orange	calcium salts calcium chloride, CaCl 2 calcium sulfate, CaSO 4 ·xH 2 O, where x = 0,2,3,5
Gold	incandescence of iron (with carbon), charcoal or lampblack
Yellow	sodium compounds sodium nitrate, NaNO 3 , cryolite, Na 3 Al F 6
Electric White	white-hot metal, such as magnesium or aluminium
Green	barium oxide, BaO Green barium compounds + chlorine producer barium chloride, BaCl + = bright green
Blue	barium oxide, BaO Green barium compounds + chlorine producer barium chloride, BaCl + = bright green
Purple	mixture of strontium (red) and copper (blue) compounds