Pyrotechnic composition for fireworks free of heavy metals

摘要

The pyrotechnic assembly that simultaneously generates the effect of lightning with crackling noises contains a metal or metal alloy of magnesium and/or aluminium in powder form and sulphate or thiosulphate as oxidising agent. Also claimed is the production of the above composition by mixing finely divided anhydrous sulphate and/or thiosulphate and the metal powder with sufficient water to form a paste containing the dihydrate of the sulphate or thiosulphate.