Fireworks gunpowder effects

Clearly gunpowder has played a prominent role in the construction of early fireworks but, unless it was used in conjunction with other pyrotechnic mixtures, the range of effects was very limited. However, it continued to be the main performer in fireworks until the introduction... 

Smoke shells and rockets are used to produce smoke clouds for military signaling and, in daylight fireworks, for ornamental effects. The shell case or rocket head is filled with a fine powder of the desired color, which powdered material need not necessarily be one which will tolerate heat, and this is dispersed in the form of a colored cloud by the explosion of a small bag of gunpowder placed as near to its center as may be. Artificial vermilion (red), ultramarine (blue), Paris green, chrome yellow, chalk, and ivory black are among the materials which have been used, but almost any material which has a bright color when powdered and which does not cake together may be employed. 

The compositions by R.Lancaster(P.Lancaster Fireworks, principles and practice,p.89(1972)) contain gunpowder(black powder), sulphur, potassium nitrate, charcoal etc., and the twinkling or glittering effect might be caused by the Senko-Hanabi reaction of the cinder. 

Many of the effects used in fireworks involved potassium nitrate, sulfur, and charcoal reactants burning to produce potassium sulfide melt as the principle product. Gunpowder-like mixtures have been in use for approximately two thousand... 

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