Penny stars are a simple zinc based star similar to granite stars, except with a relatively short-lived greenish-white spark tail. The Zinc in this composition must be course granular or flake zinc powder; this type of zinc can be made by putting filing or grinding several post-1983 US pennies (97.5% zinc plated in 2.5% copper.)
|Penny grindings or coarse Zinc powder.||5||45.5%|
|Xanthan gum (optional)||0 to 0.5||+0% to +4.5%|
|Dextrin or SGRS (parts respective)||0.5 or 0.2||+5% or 2%|
If necessary, individually grind all chemicals (except zinc) as fine as possible using a coffee grinder or mortar and pestle. Mix all the ingredients together by screening (zinc may need to be added seperately). Next moisten the mixure with 75:25 Water-Alcohol Mixture so it can be pumped into stars. Adding 1%-2% boric acid to solvent is advise to inhibit the reaction between Zinc and nitrates which can lead to sponaneous ignition. Keep adding the solvent solution until it is damp enough to clump together when squeezed in your hand. If water runs out when squeezing, it is too wet and more dry powder must be added or else pumping will be impossible.
Xanthan Gum improves the effect significaly, but makes the composition harder to work with, slower burning, and more difficult to ignite.
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