Penny stars

From PyroGuide

Penny stars are a simple zinc based star similar to granite stars but with relatively short lived greenish white sparks. The zinc must be course granular or flake zinc powder, this zinc can be gotten by putting a penny in a vise and filing it down, catch the zinc powder on a paper plate. Pennies Pre-1983 do not contain zinc but pennies after do.

Composition

Penny Stars

Potassium nitrate	4
Zinc	5
Charcoal	1
sulfur	1
Xanthan gum (optional)	0.5

Method

If necessary, individually grind all chemicals as fine as possible , using a coffee grinder or mortar and pestle. Mix all the ingredients together; adding 1-2% boric acid is suggested to protect the reaction between the zinc and nitrates. Then using the screen method add 5% dextrin until homogeneous. The sensitivity of this composition is unknown! Now you need to moisten the mix so it can be pumped into stars. Do this by mixing up a solution of about 75% water and 25% isopropyl alcohol (do not add any more than 25% alcohol). The alcohol makes the water wetter by breaking down the surface tension of the composition and allows the water to be absorbed easier. The drying time of a composition is also reduced as alcohol evaporates faster than water.

Add some of the solution to the composition and mix well. Keep adding until it is damp enough to clump together if you squeezed an amount in your hand without any water spilling out. Don't make the mixture too wet or it will make pumping the composition impossible. If this happens, just add more dry mix.

Notes

I have only tested this composition in very small 1/8 inch stars, so the affect of the stars in reasonably sized stars may not fit the exact description. So will someone please make larger stars and correct the description.