Bismuth Trioxide is commonly used as a fuel in the composition of crackling stars, along with other chemicals such as charcoal and sulfur. Crackling stars are pyrotechnic stars that produce a crackling or popping sound when they burn. When ignited, the it reacts with the other components to produce a popping or crackling sound, creating the desired effect.
In addition to its use as a fuel, it can also be used as a colorant in crackling stars to produce colored sparks along with the crackling sound.
Harmful by inhalation, in contact with skin and if swallowed. Wear suitable protective clothing when working with it, such as dust mask and latex gloves.