Editing Thermite (section)

== Ignition ==
{{stack|[[Image:ThermiteFe2O3.JPG|thumb|A thermite reaction using iron(III) oxide]]}}
[[Metal]]s, under the right conditions, burn in a process similar to the [[combustion]] of wood or gasoline. In fact, rust is the result of [[oxidation]] of [[steel]] or iron at very slow rates. A thermite reaction results when the correct mixtures of metallic fuels combine and ignite. Ignition itself requires extremely high temperatures.<ref>{{Cite book |last1=Kosanke |first1=K. L. |url=https://books.google.com/books?id=AK8zAwAAQBAJ |title=Encyclopedic Dictionary of Pyrotechnics: (and Related Subjects) |last2=Sturman |first2=Barry T. |last3=Winokur |first3=Robert M. |last4=Kosanke |first4=B. J. |date=2012 |publisher=Journal of Pyrotechnics |isbn=978-1-889526-21-8 |pages=1114 |language=en}}</ref>

Ignition of a thermite reaction normally requires a [[sparkler]] or easily obtainable magnesium ribbon, but may require persistent efforts, as ignition can be unreliable and unpredictable. These temperatures cannot be reached with conventional [[black powder]] [[fuse (explosives)|fuses]], [[nitrocellulose]] rods, [[detonator]]s, [[pyrotechnic initiator]]s, or other common igniting substances.<ref name="amazingrust"/> Even when the thermite is hot enough to glow bright red, it does not ignite, as it has a very high ignition temperature.<ref>{{Cite web |last=Helmenstine |first=Anne Marie |date=2019-12-08 |title=How to (Safely) Perform a Thermite Reaction |url=https://www.thoughtco.com/thermite-reaction-instructions-and-chemistry-604261 |url-status=live |archive-url=https://web.archive.org/web/20230108151257/https://www.thoughtco.com/thermite-reaction-instructions-and-chemistry-604261 |archive-date=2023-01-08 |access-date=2023-02-24 |website=[[Dotdash Meredith|ThoughtCo]]}}</ref> Starting the reaction is possible using a [[propane torch]] if done correctly.<ref>{{cite web |url=http://www.nakka-rocketry.net/thermites.html |title=Richard Nakka's Experimental Rocketry Site |publisher=Nakka-rocketry.net |access-date=2011-10-12 |first=Richard |last=Nakka |date=2007-05-02 }}</ref>

Often, strips of [[magnesium]] metal are used as [[Fuse (explosives)|fuses]]. Because metals burn without releasing cooling gases, they can potentially burn at extremely high temperatures. Reactive metals such as magnesium can easily reach temperatures sufficiently high for thermite ignition. Magnesium ignition remains popular among amateur thermite users, mainly because it can be easily obtained,<ref name="amazingrust"/> but a piece of the burning strip can fall off into the mixture, resulting in premature ignition.{{fact|date=March 2023}}

The reaction between [[potassium permanganate]] and [[glycerol]] or [[ethylene glycol]] is used as an alternative to the magnesium method. When these two substances mix, a spontaneous reaction begins, slowly increasing the temperature of the mixture until it produces flames. The heat released by the oxidation of glycerine is sufficient to initiate a thermite reaction.<ref name="amazingrust"/>

Apart from magnesium ignition, some amateurs also choose to use sparklers to ignite the thermite mixture.<ref>{{cite web |url=http://www.abc.net.au/worldtoday/content/2004/s1205680.htm |title=The World Today – Virgin Blue security scare |publisher=Abc.net.au |date=2004-09-23 |access-date=2011-10-12 |archiveurl=https://web.archive.org/web/20050115145911/http://www.abc.net.au/worldtoday/content/2004/s1205680.htm |archivedate=2005-01-15 |first=David |last=Hardaker }}</ref> These reach the necessary temperatures and provide enough time before the burning point reaches the sample.<ref>{{cite web |last=Gray |first=Theodore |url=http://www.popsci.com/node/2865 |archive-url=https://archive.today/20120908004503/http://www.popsci.com/node/2865 |url-status=dead |archive-date=2012-09-08 |title=Making Steel with Beach Sand &#124; Popular Science |publisher=Popsci.com |date=2004-08-19 |access-date=2011-10-12 }}</ref> This can be a dangerous method, as the iron [[Spark (fire)|sparks]], like the magnesium strips, burn at thousands of degrees and can ignite the thermite, though the sparkler itself is not in contact with it. This is especially dangerous with finely powdered thermite.{{fact|date=March 2023}}

Match heads burn hot enough to ignite thermite. Use of match heads enveloped with aluminum foil and a sufficiently long viscofuse/electric match leading to the match heads is possible.{{fact|date=March 2023}}

Similarly, finely powdered thermite can be ignited by a [[flint spark lighter]], as the sparks are burning metal (in this case, the highly reactive [[rare-earth metals]] [[lanthanum]] and [[cerium]]).<ref>{{cite web |url=http://www.shurlite.com/msds.pdf |title=Material Safety Data Sheet Lighter Flints Ferro Cerrium |publisher=shurlite.com |date=2010-09-21 |access-date=2012-01-22 |archive-date=2015-08-24 |archive-url=https://web.archive.org/web/20150824054802/http://www.shurlite.com/msds.pdf |url-status=dead |author=Shurlite }}</ref> Therefore, it is unsafe to strike a lighter close to thermite.{{fact|date=March 2023}}