Although this composition is fairly insensitive, it should be treated with care and respect. Hobbyist pyrotechnicians usually use a method called diapering, in which the materials are poured separately onto a large piece of paper, which is then alternately lifted at each corner to roll the composition over itself and mix the components. Some amateur pyrotechnicians choose to mix the composition by shaking in a closed paper container, as this is much quicker and more effective than diapering. One method of mixing flash is to put the components in the final device and handling the device will mix the flash powder. Paper/cardboard is chosen over other materials, such as plastic, as a result of its favorable triboelectric properties. Large quantities should never be mixed in a single batch. Large quantities are not only more difficult to handle safely, but they place innocent bystanders within the area at risk. In the event of accidental ignition, debris from a multiple-pound flash powder explosion can be thrown hundreds of feet with sufficient force to kill or injure. (Note: 3 grams of mixture is enough to explode in open air without constraint other than air pressure.) No matter the quantity, care must always be taken to prevent any electrostatic discharge or friction during mixing or handling, as these may cause accidental ignition. Magnesium and nitrate Another flash composition common among amateurs consists of magnesium powder and potassium nitrate. Other metal nitrates have been used, including barium and strontium nitrates. Compositions using nitrate and magnesium metal have been used as photographic flash powders almost since the invention of photography. Potassium nitrate/magnesium flash powder should be mixed and used immediately and not stored due to its tendency of self-ignition. If magnesium isn't a very fine powder it can be passivated with linseed oil or potassium dichromate. The passivated magnesium flash powder is stable and safe to store. 2 KNO3 + 5 Mg → K2O + N2 + 5 MgO The composition is 62.5% KNO3 : 37.5% Mg by weight for the reactants of the above stoichiometrically balanced equation. Below is the same reaction but involving barium nitrate. Ba(NO3)2 + 5 Mg → BaO + N2 + 5 MgO Mixtures designed to make reports are substantially different from mixtures designed for illumination. A stoichiometric ratio of three parts KNO3 to two parts Mg is close to ideal and provides the most rapid burn. The magnesium powder should