You’ve likely seen bang-snaps around New Year’s or Independence Day or played with them as a kid. They’re the tiny teardrop-shaped paper firecrackers that pop like a cap gun when you toss them on the ground. That pop, or detonation, is made possible with silver. When metallic silver is dissolved in nitric acid, the result is silver nitrate. Silver nitrate mixed with ethanol creates silver fulminate – a highly volatile compound that is added to grains of gravel to make bang-snaps.
If you set off a few bang-snaps in-between your fingers, you can actually see the silver shimmering within the leftover residue. Believe it or not, it’s actually possible to extract and refine the silver from these little fireworks. The process is a bit similar to the one we use to refine the filing dust and bench sweeps that jewelers bring to our shop. Essentially:
1. Remove all the paper from the bang-snaps so only the silver-laden gravel remains
2. Soak the gravel in a mixture of distilled water and nitric acid
3. Remove the gravel and precipitate the solids from the acid solution
4. Mix the solids with some flux, place in a crucible, and heat to at least 1763ºF
5. Take the resulting lead/silver alloy and reheat in a cupel until only silver remains
The YouTube channel “Cody’s Lab” has a great video that shows the process in detail – extracting 1.14 grams of silver from 5,000 bang-snaps. It may not be cost-effective, but it sure is fascinating! Please do not try this at home, dealing with chemicals like nitric acid can be very dangerous.
