Acetone, 2-propanon

Formula: C3H6O

Description: Acetone is a very volatile flammable liquid which is commonly used as a solvent. Nitrocellulose and red gum both dissolve very well in acetone. The solution of nitrocellulose is called nitrocellulose lacquer. Working with acetone can be difficult as compositions dry out very quickly. The evaporation of the acetone also causes cooling of composition, sometimes even below 0 deg C. This can result in condensation of water.

Hazards: Acetone is very volatile and flammable. Acetone vapour is heavier than air and spreads over the ground. Only work with acetone outside or in a well ventilated area.

Sources: Acetone can usually be bought at any paint store. Making acetone at home is very impractical and unneccessary as it can be bought just about anywhere at low cost.

Antimony trisulfide, realgar

Formula: Sb2S3

Description: Antimony trisulfide is a fuel which is sometimes used in glitter compositions, fountain compositions and flash powder. For the latter purpose however it is used less and less as it is very poisonous and can usually be replaced by sulfur or completely ommited. Flash compositions containing antimony trisulfide are very sensitive to friction, shock, and static electricity.

Hazards: Antimony trisulfide should never be used in any mixture containing chlorates or spontaneous ignition may occur. Mixtures with antimony trisulfide and perchlorates are very sensitive to friction and shock and extra caution should be exercised when handling these mixtures. These mixtures are best avoided at all. Wear proper protective clothing including a dust mask, when working with compositions containing antimony trisulfide as it is very poisonous.

Sources: Antimony trisulfide is sometimes sold as a pigment in (art) paint stores, but is not used very commonly these days due to it's toxicity. It can be made at home by fusing a stochiometric mixture of antimony metal and sulfur. This is a very dangerous operation since extremely toxic fumes will form and it should only be performed with proper safety precautions taken.

Aluminum

Formula: Al

Description: Aluminum powder is one of the most often used fuels in pyrotechnics. A wide range of effects are possible with different types of powder, depending on particle size, shape and impurities. The finest powders (sometimes reffered to as 'dark' aluminum) such as the well known 'german dark' are used mainly in flash. Fine aluminum is also used in small percentages in some rocket fuels. Coarser powders are generally used for spark effects. Depending on the particles shapes, sizes and compositions many different effects such as flitter, glitter, firefly and snowball can be achieved.

Hazards: A dust mask should be worn when working with aluminum powder. Mixtures containing nitrates and aluminum powder are prone to heating up spontaneously and may ignite, especially when wet. This is caused by the reduction of the nitrate by aluminum, forming amides. These very basic compounds react further with aluminum powder in a very exothermic reaction that can cause spontaneous ignition. An ammonia smell is often produced in this reaction. Adding 1 to 2% boric acid to compositions containing nitrates and aluminum is common practice and will often prevent spontaneous ignition, although this should never be relied upon. It is advisable to avoid using water to bind such compositions. Red gum or shellac with alcohol or nitrocellulose lacquer are preffered binder and solvents.

Sources: Aluminum powder is sometimes sold as a pigment in (art) paint stores. This powder, known as 'aluminum bronze', is a flaky powder with a stearin coating. It is quite expensive but readily available and a source for small quantities. Aluminum grit and turnings can sometimes be found in machine shops were aluminum is processed. If fine enough this can be used as is, but it can also be ball milled into flakes. These flakes are quite reactive as they have a large surface area and can be used for several effects. Aluminum powder can also be made by sanding aluminum chunks. I've heard of people building a machine to do this, and the results can be quite good depending on the sanding paper used and the setup.

Ammonium chloride

Formula: NH4Cl

Description: Ammonium chloride is used in smoke compositions. When heated ammonium chloride decomposes to HCl and NH3, both gasses. These recombine in the air to give a smoke consisting of fine particles of ammonium chloride.

Hazards: Ammonium chloride based smoke is irritating to the eyes and lungs as it contains some remaining HCl and NH3. Ammonium chloride itself is not poisonous and is even used in some type of candy. Ammonium chloride is an exception to the rule that ammonium compounds should never be mixed with chlorates. In most mixtures that would result in the formation of ammonium chlorate which is likely to result in spontaneous ignition. Ammonium chloride can be used in mixtures containg potassium chlorate since potassium chlorate is much less soluble than ammonium chlorate. Hence no double decomposition reaction will occur.

Sources: Ammonium chloride solution is easily prepared by neutralising ammonia solution with hydrochloric acid. It is advised to use a slight excess of ammonia. That is to make sure no remaining acid will be present in the ammonium chloride obtained on evaporation and crystallisation. Otherwise traces of the acid solution may be enclosed in the crystals, possibly leading to spontaneous ignition of mixtures made with it.

Ammonium nitrate

Formula: NH4 NO3

Description: Ammonium nitrate is an oxidiser. It is very hygroscopic and therefore not used very often in fireworks. It finds some use in composite propellants, but performance is not as good as perchlorate based propellants.

Hazards: Large masses of ammonium nitrate have been known to explode on some occasions although it is very unsensitive. Smaller quantities are less likely to detonate. The risk of detonation increases when ammonium nitrate is molten or mixed with fuels such as metal powders or organic substances. Ammonium nitrate should never be mixed with chlorates as this may result in ammonium chlorate formation, possibly leading to spontaneous ignition. Mixtures of metal powders and ammonium nitrate are likely to heat up spontaneously and may ignite, especially when moist. This can sometimes be prevented by the addition of small amounts of boric acid (1 to 2%), but in general it is better to avoid these mixtures at all. The hygroscopic nature of ammonium nitrates makes this problem worse (also see aluminum).

Sources: Ammonium chloride solution can be prepared by neutralising ammonia solution with nitric acid. It is advised to use a slight excess of ammonia. That is to make sure no remaining acid will be present in the ammonium nitrate obtained on evaporation and crystallisation. Otherwise traces of the acid solution may be enclosed in the crystals, possibly leading to spontaneous ignition of mixtures made with it. Large quantities of ammonium nitrate can also be cheaply bought as fertilizer. In the Netherlands a fertilizer called 'kalkammonsalpeter' is sold. This consists of ammonium nitrate mixed with 'mergel', a mineral consisting mainly of calcium carbonate. The ammonium nitrate can be extracted with water.

Ammonium perchlorate

Formula: NH4ClO4

Description: Ammonium perchlorate is an oxidiser used in a large number of compositions. Very impressive color compositions can be made with it, but their burn rate is often too low for use in star compositions. For lancework and torches slow burning is an advantage and it is therefore commonly used in these items. Ammonium perchlorate is also used in composite rocket propellants, including the propellants used in the solid propellant boosters used for the space shuttle. The decomposition products of ammonium perchlorate are all gasses which is very beneficial for rocket propellants.

Hazards: Ammonium perchlorate can detonate by itself, although it is not very sensitive. Larger amounts and mixtures of ammonium perchlorate with metal powders or organic substances are more likely to detonate.

Sources: Ammonium perchlorate is usually bought from chemical suppliers and from dedicated pyro suppliers such as skylighter. Fine ammonium perchlorate powder is a regulated substance in most countries and cannot easily be bought or transported. Since it is such a usefull chemical in pyrotechnics it can be worth the time and effort to try to prepare it at home. This can be done by first making sodium perchlorate followed by double decomposition with ammonium chloride (other ammonium compounds can be used). The preparation of sodium perchlorate is most easily accomplished by electrolysis, the procedure for which is described elsewhere on this page.

Barium carbonate

Formula: BaCO3

Description: Barium carbonate is used both in white and green color compositions. When chlorine donors are present in a composition a green color will result from the formation of BaCl+ in the flame. Without chlorine donors BaO will be formed which emits white light. Barium carbonate is convenient to use in chlorate based color compositions since it will neutralize residual acid which reduces the risk of spontaneous ignition.

Hazards: Most barium compounds are very poisonous, especially the more soluble barium compounds such as the chlorate and nitrate. A dust mask should be worn at all times when working with barium carbonate.

Sources: Barium carbonate is cheaply available in kilogram quantities from ceramic supply shops. However, this material is often contaminated with small amounts of barium sulfide which are left over from the production process. Therefore, ceramics grade barium carbonate should never be used in mixtures incompatible with sulfides such as chlorate based mixtures. Barium carbonate is not easily made at home.

Barium chlorate

Formula: BaClO3

Description: Barium chlorate is used as an oxidiser in green color compositions. Fierce burning and high color purity compositions can be made with it.

Hazards: Barium chlorate is poisonous and a dust mask should be worn at all times when handling it. Barium chlorate should never be mixed with sulfur or sulfides or allowed to come in contact with mixtures containg sulfur or sulfides since this could result in spontaneous ignition. (Sulfur reacts with water and air to form small amounts of sulfuric acid. Sulfuric acid and chlorates react producing ClO2, an explosive gas which will ignite many organic materials on contact). Mixtures made with barium chlorate are often especially sensitive to friction and shock (even more so than potassium chlorate based mixtures) and should be handled with extra care.

Sources: Barium chlorate is usually purchased from chemical suppliers and from dedicated pyro suppliers such as skylighter. It can be made at home from sodium chlorate and barium chloride by double decomposition. Barium chlorate can also be prepared from barium chloride by electrolysis in a process analogous to that used for preparing sodium chlorate.

Barium nitrate

Formula: BaNO3

Description: Barium nitrate is used as an oxidiser in both white and green color compositions. When chlorine donors are present in a composition a green color will result from the formation of BaCl+ in the flame. Without chlorine donors BaO will be formed which emits bright white light. Barium nitrate is seldom used as the sole oxidiser in green color compositions. It is usually combined with perchlorates to improve the color and increase the burning rate.

Hazards: Barium nitrate is poisonous and a dust mask should be worn at all times when handling it. Mixtures of metal powders and barium nitrate sometimes heat up spontaneously and may ignite, especially when moist. This can usually be prevented by the addition of small amounts of boric acid (1 to 2%). It is advisable to avoid using water to bind such compositions. Red gum or shellac with alcohol or nitrocellulose lacquer are preffered binder and solvents (also see aluminum).

Sources: Barium chlorate can be made at home from sodium chlorate and barium chloride by recrystallisation. It can also be prepared from barium chloride by electrolysis in a process analogous to that used for preparing sodium chlorate.

Boric acid

Formula: H3BO3

Description: Boric acid is a white powder which is used as an additive to compositions containing aluminum or magnesium and a nitrate. The metal powder can reduce the nitrate to an amide which will react with the metal powder in a very exothermic reaction that can lead to spontaneous ignition of the composition. This process is often accompanied by a smell of ammonia and is most likely to occur with wet compositions. Addition of a few percent boric acid can often prevent this reaction from taking place since it neutralizes the very basic amides forming ammonia and a borate. It is also advisable to avoid using a water soluble binder for these composition. Using red gum or shellac with alcohol or nitrocellulose lacquer is safer. Boric acid will also impart a green color to a flame but is hardly ever used in color compositions since barium compounds in combination with a chlorine donor produce much more spectacular colors.

Hazards: Boric acid is not particularly toxic or dangerous.

Sources: Boric acid is cheaply and in kilogram quantities available from ceramic supply shops. It is also sold in many drug stores at a somewhat higher price, but since only small quantities are needed the price is not really important.

Boric acid

Formula: H3BO3

Description: Boric acid is a white powder which is used as an additive to compositions containing aluminum or magnesium and a nitrate. The metal powder can reduce the nitrate to an amide which will react with the metal powder in a very exothermic reaction that can lead to spontaneous ignition of the composition. This process is often accompanied by a smell of ammonia and is most likely to occur with wet compositions. Addition of a few percent boric acid can often prevent this reaction from taking place since it neutralizes the very basic amides forming ammonia and a borate. It is also advisable to avoid using a water soluble binder for these composition. Using red gum or shellac with alcohol or nitrocellulose lacquer is safer.

Hazards: Boric acid is not particularly toxic or dangerous.

Sources: Boric acid is cheaply and in kilogram quantities available from ceramic supply shops. It is also sold in many drug stores at a somewhat higher price, but since only small quantities are needed the price is not really important.

Calcium sulphate

Formula: CaSO4.x H2O where x= 0, 2, 3 or 5

Description: The trihydrate is commonly known as plaster of paris. The dihydrate occurs as a mineral known as gypsum . Calcium sulphate can be used as a high temperature oxidiser in orange color compositions. Excellent strobe compositions can be made with it.

Hazards: Calcium sulphate is not particularly toxic or dangerous.

Sources: Plaster can be used as is in strobe compositions, but is better to remove the water which is easily accomplished by heating.

Charcoal

Formula: mixture with variable composition.

Description: Charcoal finds widespread use in pyrotechnics. Many types of charcoal exist, each with its own properties. Charcoal made from willow or grapevine is considered great for black powder, while paulownia and pine charcoal are commonly used for spark effects. The particle size and the process used to make the charcoal also play an important role in the quality of the charcoal for a specific purpose. Very fine charcoal floats in air and is therefore sometimes referred to as 'airfloat'.

Hazards: Fine charcoal dust is easily breathed in a dust mask should be worn when working with fine charcoal. Freshly prepared charcoal can be pyrophoric even when not powdered and it must be allowed to stand for a day at least before it is used to prepare compositions with.

Sources: Barbeque briquettes are mixed with clay and are not suitable for making black powder. It will however produce long lasting sparks and can be used for that purpose. Charcoal is easily prepared at home, although it can be hard to get reproducible results. Simply placing some twigs (1 to 2 cm diameter) in a steel pan with a lid and heating it on a camping stove will make reasonable quality charcoal. It is important to make sure you don't heat for too long. Good charcoal looks like the original twigs but black with a brown tinge. It should not have split lengthwise and it should break easily with a sharp snap. The rings in the wood should still be visible. It is possible to tell when the charcoal is done by the smoke emerging from the pan. During 'pyrolysis', the process of heating the wood in the absence of oxygen, smoke will form. After some time less smoke will form and that's the time to stop heating. Leave the lid on the pan while the charcoal cools to exclude air.

Charcoal

Formula: mixture with variable composition.

Description: Charcoal finds widespread use in pyrotechnics. Many types of charcoal exist, each with its own properties. Charcoal made from willow or grapevine is considered great for black powder, while paulownia and pine charcoal are commonly used for spark effects. The particle size and the process used to make the charcoal also play an important role in the quality of the charcoal for a specific purpose. Very fine charcoal floats in air and is therefore sometimes referred to as 'airfloat'.

Hazards: Fine charcoal dust is easily breathed in, and a dust mask should be worn when working with it. Freshly prepared charcoal can be pyrophoric even when not powdered and it must be allowed to stand for a day at least before it is used to prepare compositions with.

Sources: Barbeque briquettes are mixed with clay and are not suitable for making black powder. It will however produce long lasting sparks and can be used for that purpose. Charcoal is easily prepared at home, although it can be hard to get reproducible results. Simply placing some twigs (1 to 2 cm diameter) in a steel pan with a lid and heating it on a camping stove will make reasonable quality charcoal. It is important to make sure you don't heat for too long. Good charcoal looks like the original twigs but black with a brown tinge. It should not have split lengthwise and it should break easily with a sharp snap. The rings in the wood should still be visible. It is possible to tell when the charcoal is done by the smoke emerging from the pan. During 'pyrolysis', the process of heating the wood in the absence of oxygen, smoke will form. After some time less smoke will form and that's the time to stop heating. Leave the lid on the pan while the charcoal cools to exclude air. Freshly made charcoal can be pyrophoric and it is certainly a good idea to leave the cooled charcoal exposed to the air for a day or two before further processing.

Colophonium

Formula: Mixture of compounds.

Description: Colophonium is an alcohol soluble resin which is sometimes used as a binder. It is not used very often since it is expensive and doesn't have much adhesion capacity.

Hazards: Colophonium is not particularly toxic or dangerous.

Sources: Artist paint stores often sell colophonium. It is also used by violin players and in the paper industry.

Copper acetoarsenite, Paris green

Formula: Cu3As2O3Cu(C2H3O2) 2

Description: Copper acetoarsenite is a green powder which is used in blue color compositions. It can produce great blues but it is also very poisonous and is used less and less for that reason. Today alternatives are available that will produce deep blues with less poisonous and cheaper compounds.

Hazards: Copper acetoarsenite is very poisonous and should only be handled wearing a dust mask. Smoke from compositions containing this compound should not be inhaled. It is best to avoid the use of this compound altogether as several safer alternatives have become available in the past decades.

Sources: Copper acetoarsenite was used in the past as a pigment known as emerald green, kings green or vienna green. Nowadays it is no longer used and it is very hard to find a paint supplier that still has it. It can be prepared at home but extreme caution must be excercised since arsenic compounds are very poisonous. The following preparation originates from Shimizu: "300 g of copper sulphate is dissolved in 1000 ml water, to which 250 g of glacial acetic acid is added; This solution is named 'A'. Then 200 g of sodium carbonate and 200 g of ersenious acid are added to 1000 ml water and boiled to form a solution, this is named 'B'. B is added little by little to A with constant stirring. Carbon dioxide gas is generated with active bubbling. When all the solution B has been added, it is boiled for about 30 minutes, when copper acetoarsenite appears gradually as green particles in the solution. The mother liquor is removed by vacuum filtration, and then green substance, copper acetoarsenite, is washed with water untill the sulphate ion dissapears; it is then dried. The yield is about 180 g."

Copper benzoate

Formula: Cu(C6H5COO)2

Description: Copper benzoate is a fuel which is used in some blue color compositions. It is not used very often as it is more expensive than most alternatives.

Hazards: Copper benzoate is poisonous and should be handled wearing a dust mask

Sources: Copper benzoate is easily prepared at home from a solution of sodium or potassium benzoate and a soluble copper salt. When these solutions are added together a green precipitate of copper benzoate forms. This is filtered, thoroughly rinsed with hot water and left to dry.

Copper chromite

Formula: ?

Description: Copper chromite is employed as a catalyst is certain rocket propellants. It is typically added in 1 to 5% quantities to whistle or composite rocket fuels which increases the burn rate. A range of other catalysts exist which can often be substituted for copper chromite. Examples are Fe2O3 and MnO2

Hazards: Copper chromite is poisonous and should be handled wearing a dust mask.

Sources: Copper chromite is very hard to make or obtain other than from dedicated pyro chemicals suppliers.

Copper(II)oxide

Formula: CuO

Description: Copper oxide is a black powder employed in blue color compositions in combination with chlorine donors.

Hazards: Copper(II)oxide is poisonous and should be handled wearing a dust mask.

Sources: Copper(II)oxide is usually available from ceramic suppy stores. It is also easily prepared at home as follows: Add a solution of sodium or potassium hydroxide to a solution of a soluble copper(II) compound (copper sulfate for example). This will yield a blue gel-like precipitate of copper(II)hydroxide. Then bring to solution to a boil. The precipitate will turn black and powdery. Boil for a minute or two to complete the reaction and allow the black copper(II)oxide precipitate to settle. Then decant the liquid. Add some boiling hot water to the precipite, stir and allow to settle again. Then decant and repeat 5 more times. This will remove all soluble impurities from the copper(II)oxide. Then the precipitate is filtered and allowed to dry.

Dextrine

Formula: mixture of polysacharides

Description: Dextrine is one of the most commonly used binders in pyrotechincs as it is very cheap and readily available. It is water soluble and can produce rock hard stars.

Hazards: Colophonium is not particularly toxic or dangerous.

Sources: Dextrine is easily prepared from starch. Potatoe and corn starch will both work fine. The starch is spread out on a sheet in a layer about 1 cm thick and placed in the oven. The oven is then heated to 220¨ÉC for several hours. The dextrine will turn slightly yellowish brown. One way to check if all the starch has been converted is to dissolve a small sample in boiling hot water and add a drop of KI3 solution. A blue color indicates presence of starch, which means the conversion hasn't completed yet. KI3 solution is conveniently prepared by dissolving a crystal of elemental iodine in a potassium iodide solution.

Iron

Formula: Fe

Description: Iron powder is used for spark effects, mainly in fountains and sparklers. It produces golden yellow branching sparks. Not every iron alloy will work equally well. Iron alloys with a high carbon content generally work best. Stainless steel will produce hardly any sparks.

Hazards: Iron needs to be protected before use in pyrotechnic compositions. Otherwise it will corrode and render the composition useless or even dangerous. Iron containing compositions are generally best kept dry and not bound with water soluble binders. Iron can be coated with linseed or tung oil. The latter was used in ancient China (and may still be used today). Linseed is very convenient to use and easy to obtain. Blackpowder-like compositions (ie Charcoal/sulfur/saltpeter based) with added metal, such as they are often used in fountains, are more sensitive than the composition without added metal. Extra caution, especially when pressing or ramming, should be excersised.

Sources: Iron turnings can often be had for free from places were iron is used for construction. Drilling, sawing etc produces a powder with wide range of particles. This powder is treated with mineral oil to remove oil and grease, sieved, and then coated with linseed oil.

Iron oxide (red)

Formula: Fe2O3

Description: Red iron oxide is used as a catalyst in composite and whistling rocket propellant formulations. It is also added to some glitter formulations and used for 'thermite', a mixture that produces enormous amounts of heat, forming molten iron.

Hazards: Red iron oxide is not particularly toxic or dangerous.

Sources: Common rust is not iron oxide. It is a mixture of oxides and hydroxides. A cheap source for red iron oxide is the ceramics supply shop.

Lead tetraoxide

Formula: Pb3O4

Description: Lead tetraoxide, sometimes called 'lead minium', is used to make crackling microstars. The composition is very sensitive, explosive and poisonous. It is in fact one of the most dangerous mixtures used commonly in modern pyrotechnics. An alternative mixture based on bismuth trioxide exists (which is less poisonous), but the high price of bismuth trioxide restricts its use.

Hazards: Lead tetraoxide, like most lead compounds, is extremely poisonous. Lead is an accumulative neurotoxin and extreme care should be taken to prevent direct contact. Lead tetraoxide may be absorbed by inhalation and ingestion. Wear a respirator, gloves, and protective clothing.

Sources: Lead tetraoxide may be prepared from a solution of lead nitrate and sodium hydroxide. Note that the procedure involves extremely corrosive and poisonous chemicals and should only be attempted by those who have access to (and know how to use) the right equipment and can handle the waste properly. Prepare a concentrated solution of sodium hydroxide by dissolving 300 grams of sodium hydroxide in water. The solution will heat up during this. To prevent it from boiling suddenly add only small portions at a time. When all has dissolved, allow it to cool down to room temperature. Dissolve 50 grams of lead nitrate in 200 ml of water, and slowly add the sodium hydroxide solution to this solution while stirring continuesly. A white precipitate will form first, which will turn orange when all sodium hydroxide solution has been added. Stir this solution well for another hour, and then allow the lead tetraoxide to settle. Carefully decant the supernatant, add water to the residue, stir, allow to settle and decant again. Repeat this 5 more times. Then filter and rinse the lead tetraoxide in the filter several times with hot water.

Manganese dioxide

Formula: MnO2

Description: Manganese dioxide can be used as a catalyst in composite and whistling rocket propellant formulations. A thermite-like mixture can also be made with it. The manganese dioxide thermite burns more slowly than the iron oxide based mixture with a bright white glow.

Hazards: Mangese dioxide is poisonous and leaves brown stains on glassware etc. The stains can be removed with dilute hydrochloric acid (ofcourse, only when the stained object is not attacked by it).

Sources: Mangese dioxide can be obtained from old batteries or from the ceramics supply store. The mangese dioxide in batteries is mixed with several other compounds from which it must be separated. An easy, though messy way to do this is as follows: Find a couple of depleted carbon-zinc batteries. Only carbon-zinc type batteries will do. Do not use other types such as rechargable or lithium based batteries. These, especially the rechargable ones, contain extremely dangerous and/or poisonous compounds such as cadmium, mercury and metallic lithium. Carbon-zinc batteries may contain small amounts of mercury as well, especially the older types, so precautions should be taken to prevent skin and eye contact and to prevent breathing or swallowing of dust. So: wear your dust mask, glasses, gloves and old clothing. Then carefully take the battery apart. You'll find a greyish white (zinc oxide) or metallic coating (zinc metal) inside, depending on wheter the battery is empty or not. This surrounds a black, sometimes wet, mass. This black stuff contains among other things the mangese dioxide. Peel the coating off and save the black mass. There is also a black rod inside attached to the anode. This is a graphite rod and can be safed for chlorate (and maybe perchlorate) preparations. We'll assume you use 2 batteries from here on. (if not, adjust amounts accordingly). Place the black mass in 200 ml of 30% hydrochloric acid. The manganese dioxide will slowly dissolve, giving off chlorine gas. Chlorine gas is dangerous: it attacks the lungs and is poisonous. Do this outside or better yet: in a fume hood if you have one. Allow the manganese dioxide several days to dissolve. The solution is then filtered which should yield a clear solution of manganese(III)chloride. In a separate container dissolve 200 grams of sodium hydroxide in a liter of bleach. Add the manganese(III)chloride solution slowly to the bleach/sodium hydroxide solution. This results in a brown precipitate of manganese dioxide which is filtered, rinsed several times with boiling hot water and dried.

Magnalium

Formula: Alloy of magnesium and aluminum. Sometimes written: MgAl

Description: Magnalium is a very brittle alloy of magnesium and aluminum. Some common uses are in for spark effects, in strobing compositions and in crackling stars.

Hazards: Magnalium dust is harmfull and a dust mask should be worn when handling fine dust. Mixtures containing nitrates and mangalium sometimes heat up and may ignite spontaneously, especially when moist. This can usually be prevented by treating the magnalium with potassium dichromate. This is done by boiling the magnalium in a 5% potassium dichromate solution. Adding fine potassium dichromate powder to such compositions may also help.

Sources: Magnalium can be made at home. Plan well and prepare yourself for working with molten metals that may ignite if you plan to make it at home. If the metal ignites expect it to burn very brightly and hot. Explosions are not common but may occur if the hot melt is allowed to contact water or oxidisers. Do it outside and away from anything flammable. If it ignites don't try to extuingish it but get away from the burning mass and let it burn out and cool before approaching it. Don't look directly into the burning metal as it may damage your eyes. Start by melting aluminum in a stainless steel container. The molten metal should be covered with a blanked of inert gas. In this case neither nitrogen nor carbon dioxide will function as an inert gas. It is best to get a cylinder of argon gas at a welding supply store. Using an electric furnace for the melting is very convenient and allows good control over the temperature. To the molten aluminum magnesium is added in solid form. The melt should be stirred from time to time. When all the magnesium has melted, the melt is allowed to solidify. It is then easily crushed up in smaller chunks with an heavy hammer. These chunks are crushed further and sieved. It can also be ball milled into a fine powder using steel media but this can be dangerous since the metal powder can become pyrophoric.

Magnesium

Formula: Mg

Description: Magnesium powder is used in a wide variety of compositions, both for spark effects and 'normal' fuel purposes. Relatively coarse magnalium is used for spark effects. In flares and some bright colored star compositions it functions as a normal fuel. It is superior to aluminum in color compositions since MgCl2 and MgO are more easily vaporised than the corresponding aluminum compounds. This reduces the amount of black-body radiation and improves the color purity.

Hazards: Magnesium dust is harmfull and a dust mask should be worn when handling fine dust. Mixtures containing nitrates and magnesium sometimes heat up and may ignite spontaneously, especially when moist. This can usually be prevented by treating the magnesium with potassium dichromate. This is done by boiling the magnalium in a 5% potassium dichromate solution. The magnesium will turn brown when this is done. Adding fine potassium dichromate powder to such compositions may also help.

Sources: Making magnesium at home is very difficult. Magnesium can be bought in boating supply stores. It is used to prevent corrosion of a ships hull. For that purpose it is welded to the hull. The lower position of magnesium in the electrochemical series will make the magnesium corrode before the steel will. Making such a block of magnesium into a fine powder will not be easy. Filing or cutting and ball milling may be tried. Ball milling of metals can be dangerous however since the metal can become pyrophoric.

Nitric acid

Formula: HNO3

Description: Nitric acid is not used in pyrotechnic compositions but it can be used to prepare a variety of usefull nitrates from carbonates, hydroxides, oxides or free elements. It is used in the explosives industry in the preparation of a lot of commonly used explosives (eg TNT, RDX, PETN, nitrocellulose). Most high explosives have no use in fireworks, though nitrocellulose is used in some fireworks compositions as an acetone soluble binder.

Hazards: Nitric acid is corrosive. The fumes are dangerous to the lungs, eyes and skin. Skin will be stained yellow upon contact. Avoid all contact with both liquid and fumes. Wear eye and skin protection (lab apron, gloves, safety glasses, etc). In some reactions (especially those with metals) a brown gas will develop: nitrogen dioxide. It is very toxic, corrosive and will attack your lungs badly. Only work with nitric acid with adequate ventilation and proper protective clothing. Don't use any solutions more concentrated than 60%. Don't try to prepare high explosives at home and don't allow any organic material to contact nitric acid accidentially because that may result in the formation of dangerously explosive and/or sensitive materials.

Sources: It is possible to prepare nitric acid in several ways. It can also be bought at some drug stores. Here (in the Netherlands) it is sold under it's Latin name, 'acidum nitricum'. Other places where it is sold is at professional gardening suppliers and at welding shops (it is used to passivate stainless steel after welding). One way to prepare it is by distilling a mixture of sulphuric acid and sodium nitrate. This process is dangerous and requires some equipment. This method is probably too dangerous for the average amateur pyro. Another possible method is by precipitating barium sulphate from a barium nitrate solution by adding sulphuric acid. What remains is a nitric acid solution. It should be possible to prepare quite concentrated solutions by using concentrated sulphuric acid and a saturated (-not- hot!) barium nitrate solution. It is important that the sulphuric acid is added to the barium nitrate solution and not the other way around. The mixing of the liquids will produce heat and if the barium nitrate solution is added to the sulphuric acid it could cause sudden boiling and splatting. Therefore, add the sulphuric acid slowly to the barium nitrate while constantly stirring. Allow the mixture to cool from time to time if it gets too hot. A white precipitate of barium sulphate should form. The mixture is then filtered through a sintered glass filter to obtain clear solution of nitric acid.

Nitrocellulose

Formula: nitrated cellulose, mixture of compounds

Description: Nitrocellulose is used as a binder in pyrotechnic compositions. It is also used in some items without any other oxidisers or fuels. In other fields of pyrotechnics than fireworks it is widely used as a propellant, sometimes mixed with nitroglycerine and other materials (so called double- or triple base propellants).

Hazards: Nitrocellulose can detonate in large quantities. It is also extremely flammable and must be handled as if it is a mixed composition (which it is in fact, on the molecular level, unlike most pure chemicals). Pure nitrocellulose is thermally instable and will decompose over time. Double and triple base powders contain nitroglycerine and are probably best avoided for use in fireworks.

Sources: Nitrocellulose is sold in gun shops to those with the proper licences in some countries. Double and triple base powders seem to be most common though. A less nitrated but usable form of cellulose, called celluloid, is also used in some household items: ping-pong balls. This may be a source for small amounts. Celluloid is also used for film but that is getting a little scarce these days with digital cameras taking over the market. It is probably too expensive for pyro uses anyway. Finally, it is possible to make nitrocellulose at home. The procedure is too lengthy to describe well here, but it involves treating cellulose (preferably cotton or paper) with a mixture of sulfuric acid, nitric acid and water. The product is then washed extensively and stabilised. Properly stabilising the product at home may be difficult and commercial nitrocellulose is preferred for that reason.

Potassium benzoate

Formula: KC7H5O2

Description: Potassium benzoate is commonly used in whistle compositions. It is a white powder

Hazards: Potassium benzoate is not particularly dangerous.

Sources: Potassium benzoate can be prepared from benzoic acid and potassium carbonate or hydroxide. Benzoic acid is not very soluble, but both potassium carbonate and hydroxide are. Dissolve 140.2g potassium carbonate or 56.1g potassium carbonate in 250 ml water, and add 146g benzoic acid. Bring the mixture to a boil. If potassium carbonate is used, CO2 gas will evolve. Continue boiling untill all benzoic acid has dissolved, occasionally adding some water to make up for what has evaporated. When all benzoic acid has dissolved, continue boiling untill the first crystals of potassium benzoate are observed (ie the saturation point has been reached). Then allow the solution to cool to room temperature. Potassium benzoate will crystalise in needle shaped crystals. Filter, and rinse the crystals twice with ice-cold water. The crystals may be dried in an oven at 100 deg C.

Potassium chlorate

Formula: KClO3

Description: Potassium chlorate is a very common oxidiser in pyrotechnics, even though it has some treacherous properties and other oxidisers would sometimes be safer to use. Part of the reason of its popularity in commercial pyrotechnics is that it is cheap and easily available. The large scale production of this compound made the first quality colored fireworks possible, about a century ago.

Hazards: Potassium chlorate is toxic, and breathing protection should be worn when handling fine powder. Compositions made with potassium chlorate tend to be more sensitive than those based on nitrates and perchlorates and should therefore be handled accordingly. Potassium chlorate, or any chlorate for that matter, should never be used in combination with sulfur and sulfides. Mixtures containing both are very sensitive and may spontaneously ignite. In general, when using chlorates great care should be taken to avoid contamination of other compositions or tools. Also read the general safety page for more information on this problem.

Sources:Potassium chlorate can be prepared at home. For this purpose, sodium chlorate is prepared first by electrolysis. It may also be obtained as a herbicide in some countries (France, for example) Then, by double decomposition with potassium chloride, potassium chlorate is prepared from this solution. The product is recrystallised, dried and powdered.

Potassium perchlorate

Formula: KClO4

Description: Potassium perchlorate is a very common oxidiser in pyrotechnics. Composition based on perchlorates tend to be less sensitive than those based on chlorates, and perchlorates can be used with sulfur and sulfides. For these reasons potassium perchlorate is much preferred above chlorates. Drawback is its slightly higher price.

Hazards: Potassium perchlorate is toxic, and breathing protection should be worn when handling fine powder.

Sources:Potassium perchlorate can be prepared at home. For this purpose, sodium perchlorate is prepared first by electrolysis. Then, by double decomposition with potassium chloride, potassium perchlorate is prepared from this solution. The product is recrystallised, dried and powdered.

Sodium chlorate

Formula: NaClO3

Description: Sodium chlorate is hardly ever used in pyrotechnics, since it is very hygroscopic. It finds occasional use in composite rocket propellants. It is however very usefull as a starting point in the preparation of several other (less hygroscopic) chlorates for which reason it is included here.

Hazards: Sodium chlorate is toxic, and breathing protection should be worn when handling fine powder. Compositions made with sodium chlorate tend to be more sensitive than those based on nitrates and perchlorates and should therefore be handled accordingly. Sodium chlorate, or any chlorate for that matter, should never be used in combination with sulfur and sulfides. Mixtures containing both are very sensitive and may spontaneously ignite. In general, when using chlorates great care should be taken to avoid contamination of other compositions or tools. Also read the general safety page for more information on this problem. Acidic solutions containing chlorates generate a very poisonous and explosive gas, ClO2.

Sources:Sodium chlorate can be prepared at home. It involves electrolysing a sodium chloride solution under certain circumstances. A description of the process, cell and anode design, etc. for home produciton may be found in the chlorate and perchlorate section of this page. In some countries, France for example, sodium chlorate may be obtained as a herbicide.

Sodium perchlorate

Formula: NaClO4

Description: Sodium perchlorate is hardly ever used in pyrotechnics, since it is very hygroscopic. It finds occasional use in composite rocket propellants. It is however very usefull as a starting point in the preparation of several other (less hygroscopic) perchlorates for which reason it is included here.

Hazards: Sodium perchlorate is toxic, and breathing protection should be worn when handling fine powder.

Sources:Sodium perchlorate can be prepared at home. It involves electrolysing a sodium chlorate solution under certain circumstances. A description of the process, cell and anode design, etc. for home produciton may be found in the chlorate and perchlorate section of this page.