Editing Quartz (section)

== Related silica minerals ==
{{See also|Silica minerals}}
[[File:P-T Diagram for SiO2.svg|thumb|right|upright=1.3|Pressure-temperature diagram showing the stability ranges for the two forms of quartz and some other forms of silica<ref>"Mineral Science" by Cornelis Klein; {{ISBN|0-471-25177-1}}</ref>]]
[[Tridymite]] and [[cristobalite]] are high-temperature [[Polymorphism (materials science)|polymorphs]] of SiO<sub>2</sub> that occur in high-silica [[Volcano|volcanic]] rocks. [[Coesite]] is a denser polymorph of SiO<sub>2</sub> found in some meteorite impact sites and in metamorphic rocks formed at pressures greater than those typical of the Earth's crust. [[Stishovite]] is a yet denser and higher-pressure polymorph of SiO<sub>2</sub> found in some meteorite impact sites.{{sfn|Nesse|2000|pp=201-202}} [[Moganite]] is a monoclinic polymorph. [[Lechatelierite]] is an [[Amorphous solid|amorphous]] silica [[glass]] SiO<sub>2</sub> which is formed by [[lightning]] strikes in quartz [[sand]].<ref>{{cite web |title=Lechatelierite |url=https://www.mindat.org/min-2363.html |website=Mindat.org |access-date=7 April 2021}}</ref>