Editing Flint (section)

===To ignite fire or gunpowder===
[[File:Flint spark lighter striking.jpg|thumb|A ferrocerium "flint" spark lighter in action]]

When struck against steel, a flint edge produces sparks. The hard flint edge shaves off a particle of the steel that exposes iron, which reacts with [[oxygen]] from the atmosphere and can ignite the proper [[tinder]].<ref name="angelfire">{{cite web |url=https://www.angelfire.com/journal2/firefromsteel/ |title=Fire from Steel – Custom forged fire steels from Roman through Fur Trade time periods |publisher=Angelfire.com |access-date=2013-07-21 |archive-date=25 January 2021 |archive-url=https://web.archive.org/web/20210125225311/https://www.angelfire.com/journal2/firefromsteel/ |url-status=live }}</ref>

Prior to the wide availability of steel, rocks of [[pyrite]] (FeS<sub>2</sub>) would be used along with the flint, in a similar (but more time-consuming) way. These methods remain popular in woodcraft, bushcraft, and amongst people practising traditional fire-starting skills.<ref name=Bush>{{cite web|last1=Bush|first1=Darren|work=Manly Skills, Self-Reliance, Survival|title=Traditional Firestarting Part I: How to Make Fire with Flint and Steel|date=6 January 2011|url=http://www.artofmanliness.com/2011/01/05/traditional-firestarting-part-i-how-to-make-fire-with-flint-and-steel/|publisher=Art of Manliness|access-date=27 July 2015|archive-date=9 August 2020|archive-url=https://web.archive.org/web/20200809060116/https://www.artofmanliness.com/articles/traditional-firestarting-part-i-how-to-make-fire-with-flint-and-steel/|url-status=live}}</ref><ref name="Survival Cache">{{cite web|title=Do you have 5 Ways to Make Fire?|url=http://survivalcache.com/survival-fire-starters/|website=Survival Cache|access-date=27 July 2015|archive-date=12 February 2021|archive-url=https://web.archive.org/web/20210212001339/https://survivalcache.com/survival-fire-starters/|url-status=live}}</ref>

====Flintlocks====
[[File:Firesteels assorted.jpg|thumb|upright|left|Assorted reproduction [[firesteel]]s typical of Roman to Medieval period]]

A later, major use of flint and steel was in the [[flintlock mechanism]], used primarily in [[flintlock]] firearms, but also used on dedicated fire-starting tools. A piece of flint held in the jaws of a spring-loaded hammer, when released by a trigger, strikes a [[hinged]] piece of steel ("[[frizzen]]") at an angle, creating a shower of sparks and exposing a charge of priming powder. The sparks ignite the priming powder and that flame, in turn, ignites the main charge, propelling the ball, bullet, or shot through the barrel. While the military use of the flintlock declined after the adoption of the [[percussion cap]] from the 1840s onward, flintlock rifles and shotguns remain in use amongst recreational shooters.

====Comparison with ferrocerium====

Flint and steel used to strike sparks were superseded in the 20th century by [[ferrocerium]] (sometimes referred to as "flint", although not true flint, "[[mischmetal]]", "hot spark", "metal match", or "fire steel"). This human-made material, when scraped with any hard, sharp edge, produces sparks that are much hotter than obtained with natural flint and steel, allowing use of a wider range of tinders. Because it can produce sparks when wet and can start fires when used correctly, ferrocerium is commonly included in [[survival kit]]s. Ferrocerium is used in many cigarette lighters, where it is referred to as "a flint".

====Fragmentation====

Flint's utility as a fire starter is hampered by its property of uneven expansion under heating, causing it to fracture, sometimes violently, during heating. This tendency is enhanced by the impurities found in most samples of flint that may expand to a greater or lesser degree than the surrounding stone, and is similar to the tendency of [[Thermal fracturing in glass|glass to shatter]] when exposed to heat, and can become a drawback when flint is used as a [[building material]].<ref>{{cite web |url=http://web.ukonline.co.uk/scoutnotebook/fires/cooking.html |title=Building a cooking fire |archive-url=https://web.archive.org/web/20090525115954/http://web.ukonline.co.uk/scoutnotebook/fires/cooking.html |archive-date=May 25, 2009 |work=Scout Notebook |access-date=January 30, 2018 |year=2001}}</ref>