Dragon's eggs
Encyclopedia
Dragon's eggs are fireworks
pyrotechnic star
s 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.
Fireworks
Fireworks are a class of explosive pyrotechnic devices used for aesthetic and entertainment purposes. The most common use of a firework is as part of a fireworks display. A fireworks event is a display of the effects produced by firework devices...
pyrotechnic star
Pyrotechnic star
Pyrotechnic stars are pellets or simply pieces of pyrotechnic composition which may contain metal powders, salts or other compounds that, when ignited, burn a certain colour or exude a spark effect. They are a part of all projectile-type fireworks. The most common is the aerial shell. When...
s 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
Heavy metals
A heavy metal is a member of a loosely-defined subset of elements that exhibit metallic properties. It mainly includes the transition metals, some metalloids, lanthanides, and actinides. Many different definitions have been proposed—some based on density, some on atomic number or atomic weight,...
once used, particularly lead tetroxide (Pb3O4). Nowadays, however, bismuth trioxide
Bismuth trioxide
Bismuth oxide is perhaps the most industrially important compound of bismuth. It is also a common starting point for bismuth chemistry. It is found naturally as the mineral bismite and sphaerobismoite , but it is usually obtained as a by-product of the smelting of copper and lead ores...
or bismuth subcarbonate
Bismuth subcarbonate
Bismuth subcarbonate Bi2O2, sometimes written 2CO3 is a chemical compound of bismuth containing both oxide and carbonate anions. Bismuth is in the +3 oxidation state. Bismuth subcarbonate occurs naturally as the mineral bismutite. Its structure consists of Bi-O layers and CO3 layers and is related...
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
Cake (firework)
A cake firework, also known as a multiple tube device is a firework comprising a series of roman candles, small aerial shells, or a combination of both, connected together by a high-speed fuse. Typically, the internal fusing is set to fire each tube in series, or to fire several tubes at the same...
containing mainly dragon's eggs is often noticeably heavier than a similar device containing other effects.