Editing Graphite (section)

===Occurrence===
Graphite occurs in [[metamorphic rock]]s as a result of the [[reduction (chemistry)|reduction]] of [[Sedimentary rock|sedimentary]] carbon compounds during [[metamorphism]]. It also occurs in [[igneous rock]]s and in [[meteorite]]s.<ref name=HBM/> [[Mineral|Minerals]] associated with graphite include [[quartz]], [[calcite]], [[mica]]s and [[tourmaline]]. The principal export sources of mined graphite are, in order of tonnage, [[China]], [[Mexico]], [[Canada]], [[Brazil]], and [[Madagascar]].<ref name="MineralsDatabase">{{cite web
  | title = Graphite
  | work = Minerals Database
  | publisher = Minerals Education Coalition
  | date = 2018
  | url = https://mineralseducationcoalition.org/minerals-database/graphite/
  | access-date = 9 December 2018}}</ref> Significant unexploited graphite resources also exist in [[Colombia]]'s [[Cordillera Central (Colombia)|Cordillera Central]] in the form of graphite-bearing [[schist]]s.<ref>{{Cite journal |title=Is the Central Cordillera of Colombia a potential source of graphite?: Implications for the energy transition in Colombia |journal=[[Andean Geology]] |url=http://www.andeangeology.cl/index.php/revista1/article/view/V51n2-3728/html |last1=Bustamante |first1=C. |issue=2 |volume=51 |pages=413–420 |last2=Cardona |first2=A. |date=2024 |doi=10.5027/andgeoV51n2-3728|doi-access=free |bibcode=2024AndGe..51..413B }}</ref>

In [[meteorite]]s, graphite occurs with [[troilite]] and [[silicate mineral]]s.<ref name=HBM/> Small graphitic crystals in [[meteoritic iron]] are called [[cliftonite]].<ref name=Brit/> Some microscopic grains have distinctive [[Isotope|isotopic]] compositions, indicating that they were formed before the [[Solar System]].<ref>{{cite book |last1=Lugaro |first1=Maria |author-link1=Maria Lugaro |title=Stardust From Meteorites: An Introduction To Presolar Grains |date=2005 |publisher=World Scientific |isbn=9789814481373 |pages=14, 154–157}}</ref> They are one of about 12 known types of minerals that predate the Solar System and have also been detected in [[molecular cloud]]s. These minerals were formed in the [[ejecta]] when [[supernova]]e exploded or low to intermediate-sized stars expelled their outer envelopes late in their lives. Graphite may be the second or third oldest mineral in the Universe.<ref>{{cite journal |last1=Hazen |first1=R. M. |last2=Downs |first2=R. T. |last3=Kah |first3=L. |last4=Sverjensky |first4=D. |title=Carbon Mineral Evolution |journal=Reviews in Mineralogy and Geochemistry |date=13 February 2013 |volume=75 |issue=1 |pages=79–107 |doi=10.2138/rmg.2013.75.4 |bibcode=2013RvMG...75...79H }}</ref><ref>{{cite journal |last1=McCoy |first1=T. J. |title=Mineralogical Evolution of Meteorites |journal=Elements |date=22 February 2010 |volume=6 |issue=1 |pages=19–23 |doi=10.2113/gselements.6.1.19|bibcode=2010Eleme...6...19M }}</ref>