Editing Metalloid (section)

===Pyrotechnics===
[[File:Blue Light.JPG|thumb|right|upright|Archaic [[blue light (pyrotechnic signal)|blue light signal]], fuelled by a mixture of [[sodium nitrate]], [[sulfur]], and (red) [[arsenic trisulfide]]<ref>[[#OO|Ordnance Office 1863, p.&nbsp;293]]</ref>|alt=A man is standing in the dark. He is holding out a short stick at mid-chest level. The end of the stick is alight, burning very brightly, and emitting smoke.]]
The recognised metalloids have either pyrotechnic applications or associated properties. Boron and silicon are commonly encountered;<ref name=Kos>[[#Kosanke|Kosanke 2002, p.&nbsp;110]]</ref> they act somewhat like metal fuels.<ref>[[#Ellern|Ellern 1968, pp.&nbsp;246, 326–27]]</ref> Boron is used in [[pyrotechnic initiator]] compositions (for igniting other hard-to-start compositions), and in [[delay composition]]s that burn at a constant rate.<ref name=Conkling82>[[#Conkling|Conkling & Mocella 2010, p.&nbsp;82]]</ref> [[Boron carbide]] has been identified as a possible replacement for more toxic [[barium]] or [[hexachloroethane]] mixtures in smoke munitions, signal flares, and fireworks.<ref>[[#Crow|Crow 2011]]; [[#Daily|Mainiero 2014]]</ref> Silicon, like boron, is a component of initiator and delay mixtures.<ref name=Conkling82/> Doped germanium can act as a variable speed [[thermite]] fuel.{{refn|1=The reaction involved is Ge + 2 [[MoO3|MoO<sub>3</sub>]] → GeO<sub>2</sub> + 2 [[MoO2|MoO<sub>2</sub>]]. Adding arsenic or antimony ([[extrinsic semiconductor#n-type semiconductors|n-type]] electron donors) increases the rate of reaction; adding gallium or indium ([[intrinsic semiconductor#p-type semiconductors|p-type]] electron acceptors) decreases it.<ref>[[#Schwab|Schwab & Gerlach 1967]]; [[#Yetter|Yetter 2012, p.&nbsp;81]]; [[#Lipscomb|Lipscomb 1972, pp.&nbsp;2–3, 5–6, 15]]</ref>|group=n}} [[Arsenic trisulfide]] As<sub>2</sub>S<sub>3</sub> was used in old [[blue light (pyrotechnic signal)|naval signal lights]]; in fireworks to make white stars;<ref>[[#Ellern|Ellern 1968, p.&nbsp;135]]; [[#Weingart|Weingart 1947, p.&nbsp;9]]</ref> in yellow [[smoke screen]] mixtures; and in initiator compositions.<ref>[[#Conkling|Conkling & Mocella 2010, p.&nbsp;83]]</ref> [[stibnite|Antimony trisulfide]] Sb<sub>2</sub>S<sub>3</sub> is found in white-light fireworks and in [[flash powder|flash and sound]] mixtures.<ref>[[#Conkling|Conkling & Mocella 2010, pp.&nbsp;181, 213]]</ref> Tellurium has been used in delay mixtures and in [[blasting cap]] initiator compositions.<ref name=Ellern>[[#Ellern|Ellern 1968, pp.&nbsp;209–10, 322]]</ref>

Carbon, aluminium, phosphorus, and selenium continue the theme. Carbon, in [[black powder]], is a constituent of fireworks rocket propellants, bursting charges, and effects mixtures, and military delay fuses and igniters.<ref>[[#RussellF|Russell 2009, pp.&nbsp;15, 17, 41, 79–80]]</ref>{{refn|1=Ellern, writing in ''Military and Civilian Pyrotechnics'' (1968), comments that [[carbon black]] "has been specified for and used in a nuclear air-burst simulator."<ref>[[#Ellern|Ellern 1968, p.&nbsp;324]]</ref>|group=n}} Aluminium is a common pyrotechnic ingredient,<ref name=Kos/> and is widely employed for its capacity to generate light and heat,<ref>[[#Ellern|Ellern 1968, p.&nbsp;328]]</ref> including in thermite mixtures.<ref>[[#Conkling|Conkling & Mocella 2010, p.&nbsp;171]]</ref> Phosphorus can be found in smoke and incendiary munitions, [[Armstrong's mixture|paper caps]] used in [[cap gun|toy guns]], and [[party popper]]s.<ref>[[#Conkling|Conkling & Mocella 2011, pp.&nbsp;83–84]]</ref> Selenium has been used in the same way as tellurium.<ref name=Ellern/>