Graphite

Graphite
Graphite
	Graphite specimen
General
Category	Native mineral
Formula; (repeating unit)	C
IMA symbol	Gr
Strunz classification	1.CB.05a
Crystal system	Hexagonal or Rhombohedral
Crystal class	Dihexagonal dipyramidal (6/mmm) ; Hermann–Mauguin notation: (6/m 2/m 2/m)
Space group	P63mc (buckled) P63/mmc (flat)
Unit cell	a = 2.461, c = 6.708 [Å]; Z = 4
Identification
Color	Iron-black to steel-gray; deep blue in transmitted light
Crystal habit	Tabular, six-sided foliated masses, granular to compacted masses
Twinning	Present
Cleavage	Basal – perfect on {0001}
Fracture	Flaky, otherwise rough when not on cleavage
Tenacity	Flexible non-elastic, sectile
Mohs scale hardness	1–2
Luster	Metallic, earthy
Streak	Black
Diaphaneity	Opaque, transparent only in extremely thin flakes
Specific gravity	1.9–2.3
Density	2.09–2.23 g/cm3
Optical properties	Uniaxial (−)
Pleochroism	Strong
Solubility	Soluble in molten nickel, warm chlorosulfuric acid
Other characteristics	strongly anisotropic, conducts electricity, greasy feel, readily marks
References

Graphite (/ˈɡræfaɪt/) is a crystalline allotrope (form) of the element carbon. It consists of many stacked layers of graphene, typically in the excess of hundreds of layers. Graphite occurs naturally and is the most stable form of carbon under standard conditions. Synthetic and natural graphite are consumed on a large scale (1.3 million metric tons per year in 2022) for uses in many critical industries including refractories (50%), lithium-ion batteries (18%), foundries (10%), lubricants (5%), among others (17%).^[6] Under extremely high pressures and extremely high temperatures it converts to diamond. Graphite's low cost, thermal and chemical inertness and characteristic conductivity of heat and electricity finds numerous applications in high energy and high temperature processes.^[7]

^ Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.
^ Liquid method: pure graphene production. Phys.org (May 30, 2010).
^ Graphite. Mindat.org.
^ Graphite. Webmineral.com.
^ Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C., eds. (1990). "Graphite" (PDF). Handbook of Mineralogy. Vol. I (Elements, Sulfides, Sulfosalts). Chantilly, VA: Mineralogical Society of America. ISBN 978-0962209703. Archived (PDF) from the original on 2013-10-04.
^ "Graphite global consumption share by end use and type".
^ Robinson, Gilpin R.; Hammarstrom, Jane M.; Olson, Donald W. (2017). Schulz, Klaus J.; Deyoung, John H.; Seal, Robert R.; Bradley, Dwight C. (eds.). "Graphite". doi:10.3133/pp1802J. This article incorporates text from this source, which is in the public domain.

[1] Warr, L.N. (2021). "IMA–CNMNC approved mineral symbols". Mineralogical Magazine. 85 (3): 291–320. Bibcode:2021MinM...85..291W. doi:10.1180/mgm.2021.43. S2CID 235729616.

[2] Liquid method: pure graphene production. Phys.org (May 30, 2010).

[3] Graphite. Mindat.org.

[4] Graphite. Webmineral.com.

[HBM-5] Anthony, John W.; Bideaux, Richard A.; Bladh, Kenneth W.; Nichols, Monte C., eds. (1990). "Graphite" (PDF). Handbook of Mineralogy. Vol. I (Elements, Sulfides, Sulfosalts). Chantilly, VA: Mineralogical Society of America. ISBN 978-0962209703. Archived (PDF) from the original on 2013-10-04.

[6] "Graphite global consumption share by end use and type".

[USGS_PP1802J-7] Robinson, Gilpin R.; Hammarstrom, Jane M.; Olson, Donald W. (2017). Schulz, Klaus J.; Deyoung, John H.; Seal, Robert R.; Bradley, Dwight C. (eds.). "Graphite". doi:10.3133/pp1802J. This article incorporates text from this source, which is in the public domain.

[1]

[2]

[3]

[4]

[5]

[6]

[7]