Dragon's egg
This article is about the firework component. For the science fiction novel, see Dragon's Egg. For the fantastical dragon's egg, see dragon.
Dragon's eggs are fireworks pyrotechnic stars which first burn for a period for a visual effect then explode with a loud report. Manufacture of this effect became controversial because of the heavy metals once used, particularly lead tetroxide (Pb3O4). Nowadays, however, bismuth trioxide or bismuth subcarbonate are commonly used as more environmentally friendly substitutes for lead compounds to achieve the effect, and its occurrence in fireworks displays has since become much more common.
Because of its chemical makeup, a shell or cake containing mainly dragon's eggs is often noticeably heavier than a similar device containing other effects.
References
- Croteau, Gerry; Dills, Russell; Beaudreau, Marc; Davis, Mac (2010). "Emission factors and exposures from ground-level pyrotechnics". Atmospheric Environment 44 (27): 3295. doi:10.1016/j.atmosenv.2010.05.048.
- Ledgard, Jared (2006-02-22). The Preparatory Manual of Black Powder and Pyrotechnics. ISBN 9781411685741.
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