Chlorite Group

A group of related mineral species

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Photos of Chlorite Group (2094)Recorded Ages and Analyses Discuss Chlorite Group

Chlorite Group Gallery Search Photos of Chlorite Group

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Clinochlore

Broughton talc mine, Saint-Pierre-de-Broughton, Les Appalaches RCM, Chaudière-Appalaches, Québec, Canada

Pennantite

Gambatesa Mine, Reppia, Ne, Genoa, Liguria, Italy

Clinochlore

Broughton talc mine, Saint-Pierre-de-Broughton, Les Appalaches RCM, Chaudière-Appalaches, Québec, Canada

Pennantite

Gambatesa Mine, Reppia, Ne, Genoa, Liguria, Italy

Clinochlore

Broughton talc mine, Saint-Pierre-de-Broughton, Les Appalaches RCM, Chaudière-Appalaches, Québec, Canada

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About Chlorite GroupHide

Colour:

Green to black

Lustre:

Pearly, Dull

Hardness:

2 - 3

Specific Gravity:

2.6 - 3.3

Crystal System:

Monoclinic

Name:

From the Greek chloros (χλωρός), meaning "green", in reference to its color.

First Recorded Locality:

ⓘ Gmina Strzegom, Świdnica County, Lower Silesian Voivodeship, Poland

A group of mostly monoclinic (also triclinic or orthorhombic) micaceous phyllosilicate minerals with a structure consisting of T-O-T layers with two layers having their silicate tetrahedral apices pointing towards each other, separated by an interlayer that may be simple octahedrally coordinated cations or which may be a brucite-*like* layer of two sheets of closely packed OH groups with the interstices between sheets providing the octahedral coordination site; the T-O-T layers and interlayer are bonded by electrostatic and hydrogen bonding forces; as the "a" and "b" directions of the T-O-T layer may be oriented to the interlayer "a" and "b" directions in twelve different stacking sequences, resulting in twelve different polytype possibilities (not all of which have been found in Nature yet for each species).

The general formula may be stated A_5-7T₄Z₁₈, where A = Al, Fe²⁺, Fe³⁺, Li, Mg, Mn, Cr, Ni, Zn or rarely Na, Ca while T = mostly Si, plus Al, Fe³⁺, Zn or B, and Z = O and/or OH.

The most common species in the chlorite group are clinochlore and chamosite.

The Árkai index (ÁI; Árkai, 1991) is an index for the estimation of a very low metamorphic grade in rocks, based on the evolution of chlorite. It is often used to complement the Kübler index (KI), earlier called the 'illite crystallinity' for the characterisation of pelites, and can also be applied in metabasites.

Unique IdentifiersHide

Mindat ID:

1016

Long-form identifier:

mindat:1:1:1016:6

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

Symbol	Source	Reference for Standard
Chl	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
Chl	Kretz (1983)	Kretz, R. (1983) Symbols of rock-forming minerals. American Mineralogist, 68, 277–279.
Chl	Siivolam & Schmid (2007)	Siivolam, J. and Schmid, R. (2007) Recommendations by the IUGS Subcommission on the Systematics of Metamorphic Rocks: List of mineral abbreviations. Web-version 01.02.07. IUGS Commission on the Systematics in Petrology. download
Chl	Whitney & Evans (2010)	Whitney, D.L. and Evans, B.W. (2010) Abbreviations for names of rock-forming minerals. American Mineralogist, 95, 185–187 doi:10.2138/am.2010.3371
Chl	The Canadian Mineralogist (2019)	The Canadian Mineralogist (2019) The Canadian Mineralogist list of symbols for rock- and ore-forming minerals (December 30, 2019). download
Chl	Warr (2020)	Warr, L.N. (2020) Recommended abbreviations for the names of clay minerals and associated phases. Clay Minerals, 55, 261–264 doi:10.1180/clm.2020.30

Pronunciation of Chlorite GroupHide

Pronunciation:

Play	Recorded by	Country
	Jolyon Ralph	United Kingdom

Physical Properties of Chlorite GroupHide

Lustre:

Pearly, Dull

Transparency:

Translucent, Opaque

Colour:

Green to black

Streak:

Colorless to pale green

Hardness:

2 - 3 on Mohs scale

Cleavage:

Perfect

Density:

2.6 - 3.3 g/cm³ (Measured)

Optical Data of Chlorite GroupHide

Type:

Biaxial

Pleochroism:

Visible

Age distributionHide

Recorded ages:

Paleoproterozoic to Quaternary : 2211 Ma to 0 Ma - based on 19 recorded ages.

Sample ages:

Sample ID	Recorded age	Geologic Time	Dating method
1	2.588 Ma to present day	Pleistocene	Formed in peat.
2	15.7 ± 0.2 Ma	Miocene	K-Ar
3	853 to 837 Ma	Tonian	Ar-Ar
4	1034 to 1024 Ma	Stenian	Ar-Ar
5	1713 to 1699 Ma	Statherian	Ar-Ar
6	1815 to 1801 Ma	Orosirian	Ar-Ar
7	2068 to 2050 Ma	Rhyacian	Ar-Ar
8	2211 to 2193 Ma	Rhyacian	Ar-Ar

Sample references:

ID	Locality	Reference
1	Grieves Siding prospect, Zeehan mineral field, Zeehan mining district, West Coast municipality, Tasmania, Australia	Awid-Pascual, Richelle, Kamenetsky, Vadim S., Goemann, Karsten, Allen, Neil, Noble, Taryn L., Lottermoser, Bernd G., Rodemann, Thomas (2015) The evolution of authigenic Zn–Pb–Fe-bearing phases in the Grieves Siding peat, western Tasmania. Contributions to Mineralogy and Petrology, 170 (2). 1-16 doi:10.1007/s00410-015-1167-y
2	Tonopah Mining District, San Antonio Mountains, Nye County, Nevada, USA	Silberman, M. L., Bonham, H. F. Jr., Garside, L. J., Ashley, R. P. (1978) Radiometric ages of volcanic and plutonic rocks and hydrothermal alteration-mineralization in the Tonopah Mining District and vicinity, Nye and Esmerelda Counties, Nevada. United States Department of the Interior Geological Survey Open-File Report 78-841. 1-48.
3	Silver Miller Mine, Coleman Township, Cobalt area, Cobalt-Gowganda region, Timiskaming District, Ontario, Canada	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144
4	" "	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144
5	Beaver Mine, Coleman Township, Cobalt area, Cobalt-Gowganda region, Timiskaming District, Ontario, Canada	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144
6	" "	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144
7	" "	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144
8	" "	Andrews, A. J., Masliwec, A., Morris, W. A., Owsiacki, L., York, D. (1986) The silver deposits at Cobalt and Gowganda, Ontario. II: An experiment in age determinations employing radiometric and paleomagnetic measurements. Canadian Journal of Earth Sciences, 23 (10) 1507-1518 doi:10.1139/e86-144

Chemical AnalysisHide

Oxide wt%:

	1	2	3	4	5	6	7	8	9	10
SiO₂	27.8 %	26.22 %	34.00 %	34.81 %	34.08 %	34.15 %	35.49 %	34.92 %	34.7 %	33.4 %
Al₂O₃	11.6 %	11.14 %	45.06 %	45.90 %	45.30 %	46.35 %	44.36 %	46.29 %	48.4 %	46.8 %
Fe₂O₃	19.1 %		0.45 %	0.72 %	0.19 %	0.02 %	0.12 %	0.07 %	0.1 %	1.13 %
FeO	25.5 %	44.83 %					0.24 %
MnO	1.7 %	1.74 %						0.13 %
MgO	1.4 %	1.45 %			1.02 %		1.32 %	0.24 %	0.05 %
H₂O	12.9 %	13.49 %	14.95 %						14.1 %
CaO		0.98 %	0.04 %		0.57 %	0.16 %	0.26 %	0.30 %	0.12 %
Na₂O		0.09 %	0.19 %	0.52 %	0.07 %	0.10 %	1.12 %	0.14 %	1.01 %	0.10 %
K₂O		0.08 %	0.14 %				0.14 %
Li₂O			4.02 %	3.59 %	3.09 %	3.18 %	2.74 %	2.67 %	2.45 %	3.15 %
F			0.46 %	0.13 %		0.35 %
H₂O+				14.87 %	14.22 %	14.06 %	13.84 %	14.12 %		14.45 %
TiO₂					0.02 %	0.02 %
H₂O-					0.38 %	0.42 %	0.55 %	0.28 %		0.50 %
B₂O₃						0.38 %				0.18 %
BeO						1.06 %
Total:	100 %	100.02 %	99.31 %	100.54 %	98.94 %	100.25 %	100.18 %	99.16 %	100.93 %	99.71 %

Sample references:

ID	Locality	Reference	Notes
1	Tuften, Tvedalen, Larvik Commune, Vestfold, Norway	Larsen, Alf Olav (2010) Chemical analysis of the minerals of the pegmatites in the Larvik plutonic complex. Unpublished supplement to the book " The Langesundsfjord".	XRF analysis by A. O. Larsen. Fe2+ by titration. H2O by difference.
2	" "	Larsen, Alf Olav (2010) Chemical analysis of the minerals of the pegmatites in the Larvik plutonic complex. Unpublished supplement to the book " The Langesundsfjord".	EMP analysis by M. Erambert. H2O by difference.
3	Mount Rubellite Quarries, Mount Rubellite, Hebron, Oxford County, Maine, USA	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analysis from Penfield 1894 from a sample found in a pegmatite cavity. The results from the analysis corresponds well with modern analyses.
4	Buckfield, Oxford County, Maine, USA	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analysis by Landes 1925 on cookeite from pegmatite vug, associated with quartz, minor apatite and herderite. The results from the analysis corresponds well with modern analyses.
5	Dobrá Voda, Žďár nad Sázavou District, Vysočina Region, Czech Republic	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analyses, with contamination less than 1%. Sample from cavity lining in pegmatite associated with quartz, apatite, tourmaline and cassiterite
6	Muiâne pegmatite, Muiane-Naipa group, Gilé District, Zambezia Province, Mozambique	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analysis from Sahama et al., 1968. Sample from cavity lining in pegmatite with quartz. No admixtures in the analysed material.
7	Lipovka Mine, Lipovsk pegmatite field, Rezhevsky District, Sverdlovsk Oblast, Russia	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analysis from Ginzburg (1953). Sample form pegmatite.
8	Manono-Kitotolo mine, Tanganyika, DR Congo	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Wet chemical analysis from Herman et al. (1961) from pegmatite.
9	North Little Rock, Pulaski County, Arkansas, USA	Cerny, Petr (1970) Compositional variations in cookeite. The Canadian Mineralogist, 10 (4). p.636-647.	Averaged values from a series of wet chemical analyses from Miser and Milton (1964). Samples from a pegmatite.
10	Alto Ligonha Pegmatite Field, Zambezia Province, Mozambique	Freitas Tavares, A. (1973) Alteração em cookeite de alguns silicatos de Zambézia (Moçambique) [Alteration to cookeite of some silicates from Zambézia (Mozambique)], in Série B (Ciénas Geográficas e Geológicas). Memórias do Instituto de Investigação Científica de Moçambique , 9. 131-143

Crystallography of Chlorite GroupHide

Crystal System:

Monoclinic

Crystal StructureHide

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Data courtesy of the American Mineralogist Crystal Structure Database. Click on an AMCSD ID to view structure

ID	Species	Reference	Year	Locality	Pressure (GPa)	Temp (K)
0007298	Clinochlore	Zanazzi P F, Comodi P, Nazzareni S, Andreozzi G B (2009) Thermal behaviour of chlorite: an in situ single-crystal and powder diffraction study European Journal of Mineralogy 21 581-589	2009	Val Malenco, Italy	0	298
0004250	Clinochlore	Zanazzi P F, Montagnoli M, Nazzareni S, Comodi P (2006) Structural effects of pressure on chlorite: A single-crystal study American Mineralogist 91 1871-1878	2006	Alpe Reguzzolo, Val Malenco, Italy	0.0001	293
0012235	Chamosite	Walker J R, Bish D L (1992) Application of Rietveld refinement techniques to a disordered IIb Mg-chamosite Clays and Clay Minerals 40 319-322	1992	Lebanon, New Hampshire, USA	0	293
0010543	Clinochlore	McMurchy R C (1934) The crystal structure of the chlorite minerals Zeitschrift fur Kristallographie 88 420-432	1934	Miles City, Montana, USA	0	293
0007299	Clinochlore	Zanazzi P F, Comodi P, Nazzareni S, Andreozzi G B (2009) Thermal behaviour of chlorite: an in situ single-crystal and powder diffraction study European Journal of Mineralogy 21 581-589	2009	Val Malenco, Italy	0	574
0007300	Clinochlore	Zanazzi P F, Comodi P, Nazzareni S, Andreozzi G B (2009) Thermal behaviour of chlorite: an in situ single-crystal and powder diffraction study European Journal of Mineralogy 21 581-589	2009	Val Malenco, Italy	0	672
0007301	Clinochlore	Zanazzi P F, Comodi P, Nazzareni S, Andreozzi G B (2009) Thermal behaviour of chlorite: an in situ single-crystal and powder diffraction study European Journal of Mineralogy 21 581-589	2009	Val Malenco, Italy	0	775
0004251	Clinochlore	Zanazzi P F, Montagnoli M, Nazzareni S, Comodi P (2006) Structural effects of pressure on chlorite: A single-crystal study American Mineralogist 91 1871-1878	2006	Alpe Reguzzolo, Val Malenco, Italy	1.83	293
0004252	Clinochlore	Zanazzi P F, Montagnoli M, Nazzareni S, Comodi P (2006) Structural effects of pressure on chlorite: A single-crystal study American Mineralogist 91 1871-1878	2006	Alpe Reguzzolo, Val Malenco, Italy	3.14	293
0004253	Clinochlore	Zanazzi P F, Montagnoli M, Nazzareni S, Comodi P (2006) Structural effects of pressure on chlorite: A single-crystal study American Mineralogist 91 1871-1878	2006	Alpe Reguzzolo, Val Malenco, Italy	4.25	293
0004254	Clinochlore	Zanazzi P F, Montagnoli M, Nazzareni S, Comodi P (2006) Structural effects of pressure on chlorite: A single-crystal study American Mineralogist 91 1871-1878	2006	Alpe Reguzzolo, Val Malenco, Italy	4.85	293
0003597	Glagolevite	Krivovichev S V, Armbruster T, Organova N I, Burns P C, Seredkin M V, Chukanov N V (2004) Incorporation of sodium into the chlorite structure: the crystal structure of glagolevite, Na(Mg,Al)6[Si3AlO10](OH,O)8 American Mineralogist 89 1138-1141	2004		0	293
0002739	Clinochlore	Welch M D, Marshall W G (2001) High-pressure behaviour of clinochlore American Mineralogist 86 1380-1386	2001		0	293
0002314	Clinochlore	Guggenheim S, Zhan W (1999) Crystal structures of two partially dehydrated chlorites: The "modified" chlorite structure American Mineralogist 84 1415-1421	1999		0	293
0002313	Clinochlore	Guggenheim S, Zhan W (1999) Crystal structures of two partially dehydrated chlorites: The "modified" chlorite structure American Mineralogist 84 1415-1421	1999		0	293
0001949	Cookeite	Zheng H, Bailey S W (1997) Refinement of the cookeite "r" structure American Mineralogist 82 1007-1013	1997		0	293
0001192	Franklinfurnaceite	Peacor D R, Rouse R C, Bailey S W (1988) Crystal structure of franklinfurnaceite: A tri-dioctahedral zincosilicate intermediate between chlorite and mica American Mineralogist 73 876-887	1988		0	293
0000771	Clinochlore	Phillips T L, Loveless J K, Bailey S W (1980) Cr3+ coordination in chlorites: a structural study of ten chromian chlorites Siskiyou Co., Calif. American Mineralogist 65 112-122	1980		0	293
0000770	Clinochlore	Phillips T L, Loveless J K, Bailey S W (1980) Cr3+ coordination in chlorites: a structural study of ten chromian chlorites Day Book Body, N. C. American Mineralogist 65 112-122	1980		0	293
0015561	Sudoite	Aleksandrova V A, Drits V A, Sokolova G V (1973) Crystal structure of ditrioctahedral chlorite Soviet Physics Crystallography 18 50-53	1973		0	293
0000155	Sudoite	Eggleton R A, Bailey S W (1967) Structural aspects of dioctahedral chlorite American Mineralogist 52 673-689	1967		0	293
0000119	Clinochlore	Brown B E, Bailey S W (1963) Chlorite polytypism: II. Crystal structure of a one-layer Cr-chlorite American Mineralogist 48 42-61	1963		0	293
0001619	Clinochlore	Nelson D O, Guggenheim S (1993) Inferred limitations to the oxidation of Fe in chlorite: a high-temperature single-crystal X-ray study American Mineralogist 78 1197-1207	1993		0	823
0002740	Clinochlore	Welch M D, Marshall W G (2001) High-pressure behaviour of clinochlore American Mineralogist 86 1380-1386	2001		1.2	293
0002741	Clinochlore	Welch M D, Marshall W G (2001) High-pressure behaviour of clinochlore American Mineralogist 86 1380-1386	2001		2.46	293
0002742	Clinochlore	Welch M D, Marshall W G (2001) High-pressure behaviour of clinochlore American Mineralogist 86 1380-1386	2001		4.65	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Clinochlore'
loop_
_publ_author_name
'Zanazzi P F'
'Comodi P'
'Nazzareni S'
'Andreozzi G B'
_journal_name_full 'European Journal of Mineralogy'
_journal_volume 21 
_journal_year 2009
_journal_page_first 581
_journal_page_last 589
_publ_section_title
;
 Thermal behaviour of chlorite: an in situ single-crystal
 and powder diffraction study
 Note: T = 25 C
;
_database_code_amcsd 0007298
_chemical_compound_source 'Val Malenco, Italy'
_chemical_formula_sum '(Mg2.782 Fe.219) (Si1.279 Al.721) O9 H4'
_cell_length_a 5.327
_cell_length_b 9.233
_cell_length_c 14.381
_cell_angle_alpha 90.2
_cell_angle_beta 97.2
_cell_angle_gamma 89.97
_cell_volume 701.736
_exptl_crystal_density_diffrn      2.681
_symmetry_space_group_name_H-M 'C -1'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  '1/2+x,1/2+y,z'
  '-x,-y,-z'
  '1/2-x,1/2-y,-z'
loop_
_atom_site_label
_atom_site_fract_x
_atom_site_fract_y
_atom_site_fract_z
_atom_site_occupancy
_atom_site_U_iso_or_equiv
MgM1   0.00000   0.00000   0.00000   0.91300   0.00790
FeM1   0.00000   0.00000   0.00000   0.08700   0.00790
MgM2   0.00106   0.33371  -0.00003   0.91200   0.00890
FeM2   0.00106   0.33371  -0.00003   0.08800   0.00890
MgM3  -0.00033   0.16679   0.49998   0.94000   0.00850
FeM3  -0.00033   0.16679   0.49998   0.06000   0.00850
MgM4   0.00000   0.50000   0.50000   0.94600   0.00660
FeM4   0.00000   0.50000   0.50000   0.05400   0.00660
SiT1   0.23159   0.16805   0.19168   0.64000   0.00760
AlT1   0.23159   0.16805   0.19168   0.36000   0.00760
SiT2   0.73199   0.00125   0.19169   0.63900   0.00770
AlT2   0.73199   0.00125   0.19169   0.36100   0.00770
O1   0.19280   0.16750   0.07680   1.00000   0.00990
O2   0.69300   0.00050   0.07690   1.00000   0.01020
O3   0.21330   0.33500   0.23290   1.00000   0.01630
O4   0.51210   0.10080   0.23300   1.00000   0.01680
O5   0.01210   0.06870   0.23300   1.00000   0.01660
O1   0.69220   0.33360   0.07340   1.00000   0.01090
O2   0.15210  -0.00060   0.43040   1.00000   0.01520
O3   0.13820   0.33740   0.43030   1.00000   0.01580
O4   0.63860   0.16150   0.43090   1.00000   0.01470
H1   0.70900   0.33500   0.13400   1.00000   0.03700
H2   0.13200   0.00500   0.37500   1.00000   0.03700
H3   0.13100   0.33800   0.37700   1.00000   0.03700
H4   0.62000   0.16100   0.37500   1.00000   0.03700

First Recorded Occurrence of Chlorite GroupHide

First Recorded Locality:

ⓘ Gmina Strzegom, Świdnica County, Lower Silesian Voivodeship, Poland

Synonyms of Chlorite GroupHide

Chlorite

Moravite

Strigovite (of Becker and Websky)

Viridite

Other Language Names for Chlorite GroupHide

Esperanto:Kloritoj

German:Chlorit
Helminth
Pseudophit (in part)

Russian:Хлорит

Simplified Chinese:绿泥石族
绿泥石

Spanish:Chlorita

Varieties of Chlorite GroupHide

Delessite	Fe-bearing variety of clinochlore (some references also consider it a Mg-rich variety of chamosite).
Leptochlorite	A name proposed by Tschermak (1890, 1891) for those members of the chlorite group which have high ferric iron, and commonly occur in fine scales or indistinctly fibrous forms. See also orthochlorite. Considered by Hey (1954) to be mostly an oxidised iron ...
Orthochlorite	A name proposed by Tschermak (1890, 1891) for those Mg-rich members of the chlorite group which have low trivalent ions, especially ferric iron. See also leptochlorite. Also used for any of several chlorites of distinct crystallization —opposed to typi...
Oxychlorite	Obsolete name for altered, oxidised, Fe-rich chlorite. Also used more recently as a theoretical end-member: for a H-deficient, ferric component, close to tri-trioctahedral, with an O12(OH)6 anionic basis (Masci et al, 2019)
Prasolite	A soft leek-green fibrous mineral from Kilpatrick Hills, Scotland. An aluminosilicate of Mg and Fe, probably a variety of chlorite.
Tatarkaite	A hydrated silicate of aluminium, magnesium, etc. from metamorphosed limestone near the Tatarka river, tributary of the Angara river, Siberia. Tatarkaite has been shown to be chlorite near ripidolite.

Relationship of Chlorite Group to other SpeciesHide

Chlorite Group Members:

Baileychlore	Zn₅Al(AlSi₃O₁₀)(OH)₈	Tric. 1
Borocookeite	(LiAl₄◻)[BSi₃O₁₀](OH)₈	Mon. m : Bb
Chamosite	Fe²⁺₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
Clinochlore	Mg₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
Cookeite	(LiAl₄◻)[AlSi₃O₁₀](OH)₈	Mon. 2/m
Donbassite	Al_4.33(AlSi₃O₁₀)(OH)₈	Mon. 2 : B2
Franklinfurnaceite	Ca₂Fe³⁺Mn²⁺₃Mn³⁺(Zn₂Si₂O₁₀)(OH)₈	Mon. 2 : B2
Glagolevite	Na(Mg,Al)₆(AlSi₃O₁₀)(OH,O)₈	Tric. 1 : P1
Gonyerite	Mn²⁺₅Fe³⁺(Fe³⁺Si₃O₁₀)(OH)₈	Orth.
Nimite	Ni₅Al(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
Pennantite	Mn²⁺₅Al(AlSi₃O₁₀)(OH)₈	Tric.
Sudoite	Mg₂Al₃(AlSi₃O₁₀)(OH)₈	Mon. 2/m : B2/m
Vakhrushevaite	Mg₅Cr(AlSi₃O₁₀)(OH)₈	Tric. 1

Click on any node to view relationships. Formula-derived relationship network for the group members above. Use Find related species to add formula-neighbour species outside the current group view. Solid links show inferred chemical differences; dashed violet links show same-formula crystallographic differences. Hydration states are not treated as relationship changes. These relationships do not imply any real-world substitution reactions between these species.

Other InformationHide

Health Risks:

No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Chlorite Group in petrologyHide

An essential component of rock names highlighted in red, an accessory component in rock names highlighted in green.

Internet Links for Chlorite GroupHide

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References for Chlorite GroupHide

Reference List:

Gruner, John W. (1944) The kaolinite structure of amesite, (OH)8(Mg,Fe)4Al2(Si2Al2)10, and additional data on chlorites. American Mineralogist, 29 (11-12) 422-430

Hey, Max H. (1954) A new review of the chlorites. Mineralogical Magazine and Journal of the Mineralogical Society, 30 (224) 277-292 doi:10.1180/minmag.1954.030.224.01

Brindley, G. W., Gillery, F. H. (1956) X-ray identification of chlorite species. American Mineralogist, 41 (3-4) 169-186

Nelson, Bruce W., Roy, Rustom (1958) Synthesis of chlorites and their structural and chemical constitution. American Mineralogist, 43 (7-8) 707-725

Bailey, S. W.; Brown, B. E. (1962) Chlorite polytypism: I. Regular and semi random one layer structures. American Mineralogist, 47 (7-8). 819-850

Brown, B. E., Bailey, S. W. (1963) Chlorite polytypism: II. Crystal structure of a one-layer Cr-chlorite. American Mineralogist, 48 (1-2) 42-61

Marel, H. W. (1964) Identification of chlorite and chlorite-related minerals in sediments. Beiträge zur Mineralogie und Petrographie, 9 (5). 462-480 doi:10.1007/bf02650156

Shirozu, Haruo, Bailey, S. W. (1965) Chlorite polytypism: III. Crystal structure of an orthohexagonal iron chlorite. American Mineralogist, 50 (7-8) 868-885

Gottardi, G. (1967) On a systematic error in the X-ray determination of the iron content of chlorites and biotites. American Mineralogist, 52 (9-10) 1573-1574

Lister, Judith S., Bailey, S. W. (1967) Chlorite polytypism: IV. Regular two-layer structures. American Mineralogist, 52 (11-12) 1614-1631

Hayes, John B. (1970) Polytypism of Chlorite in Sedimentary Rocks. Clays and Clay Minerals, 18 (5) 285-306 doi:10.1346/ccmn.1970.0180507

Dodge, F. C. W. (1973) Chlorites from granitic rocks of the central Sierra Nevada batholith, California. Mineralogical Magazine, 39 (301) 58-64 doi:10.1180/minmag.1973.039.301.08

Velde, Bruce (1973) Phase Equilibria in the System MgO-Al₂O₃-SiO₂-H₂O: Chlorites and Associated Minerals. Mineralogical Magazine, 39 (303) 297-312 doi:10.1180/minmag.1973.039.303.06

Post, J. L. (1974) Properties of ‘Swelling’ Chlorite in Some Mesozoic Formations of California. Clays and Clay Minerals, 22 (1) 67-77 doi:10.1346/ccmn.1974.0220110

Brindley, G. W., Chang, and Tien Show (1974) Development of long basal spacings in chlorites by thermal treatment. American Mineralogist, 59 (1-2) 152-158

Wiewióra, Andrzej (1975) Nickel Containing Regularly Interstratified Chlorite-Saponite from Szklary, Lower Silesia, Poland. Clays and Clay Minerals, 23 (2) 91-96 doi:10.1346/ccmn.1975.0230202

Black, Philippa M. (1975) Mineralogy of New Caledonian metamorphic rocks. IV. Sheet silicates from the Ouégoa district. Contributions to Mineralogy and Petrology, 49 (4). p.269-284. doi:10.1007/bf00376180(chlorite stability and chemistry)

Hazen, Robert M., Finger, Larry W. (1978) The crystal structures and compressibilities of layer minerals at high pressure. II. Phlogopite and chlorite. American Mineralogist, 63 (3-4) 293-296

Ďurovič, S., Dornberger-Schiff, K., Weiss, Z. (1983) Chlorite polytypism. I. OD interpretation and polytype symbolism of chlorite structures. Acta Crystallographica Section B Structural Science, 39 (5). 547-552 doi:10.1107/s0108768183002943

Weiss, Z., Ďurovič, S. (1983) Chlorite polytypism. II. Classification and X-ray identification of trioctahedral polytypes. Acta Crystallographica Section B Structural Science, 39 (5) 552-557 doi:10.1107/s0108768183002955

Tompkins, Linda A., Bailey, S. W., Haggerty, Stephen E. (1984) Kimberlitic chlorites from Sierra Leone, West Africa: unusual chemistries and structural polytypes. American Mineralogist, 69 (3-4) 237-249

Olives Baños, Juan; Amouric, Marc (1984) Biotite chloritization by interlayer brucitization as seen by HRTEM. American Mineralogist, 69 (9-10). p.869-871.

Spinnler, G.E. (1985) HRTEM study of antigorite, pyroxene-serpentine reactions and chlorite, 248 p. Ph.D. Thesis, Arizona State University, Tempe, Arizona.

Olives Baños, Juan (1985) Biotites and chlorites as interlayered biotite-chlorite crystal. Bulletin de Minéralogie, 108 (5) 635-641 doi:10.3406/bulmi.1985.7879

Curtis, C. D., Hughes, C. R., Whiteman, J. A., Whittle, C. K. (1985) Compositional variation within some sedimentary chlorites and some comments on their origin. Mineralogical Magazine, 49 (352) 375-386 doi:10.1180/minmag.1985.049.352.08

Schreyer, W., Fransolet, A. -M., Abraham, K. (1986) A miscibility gap in trioctahedral Mn-Mg-Fe chlorites: Evidence from the Lienne Valley manganese deposit, Ardennes, Belgium. Contributions to Mineralogy and Petrology, 94 (3) 333-342 doi:10.1007/bf00371442

Bailey, S. W. (1988): Chlorites: Structures and crystal chemistry. Reviews in Mineralogy 19, 347-403.

Velde, B., Medhioub, M. (1988) Approach to chemical equilibrium in diagenetic chlorites. Contributions to Mineralogy and Petrology, 98 (1) 122-127 doi:10.1007/bf00371916

Bailey, S. W. (1989) Structures, Compositions, and X-ray Diffraction Identification of Dioctahedral Chlorites. Clays and Clay Minerals, 37 (3) 193-202 doi:10.1346/ccmn.1989.0370301

Walker, Jeffrey R. (1989) Polytypism of chlorite in very low grade metamorphic rocks. American Mineralogist, 74 (7-8) 738-743

Wiewióra, A., Weiss, Z. (1990) Crystallochemical classifications of phyllosilicates based on the unified system of projection of chemical composition: II. The chlorite group. Clay Minerals, 25 (1) 83-92 doi:10.1180/claymin.1990.025.1.09

Walker, Jeffrey R. (1990) Structural Variations in Chlorite and Illite in a Diagenetic Sequence from the Imperial Valley, California. Clays and Clay Minerals, 38 (3) 315-321 doi:10.1346/ccmn.1990.0380311

ÁRKAI, P. (1991) Chlorite crystallinity: an empirical approach and correlation with illite crystallinity, coal rank and mineral facies as exemplified by Palaeozoic and Mesozoic rocks of northeast Hungary. Journal of Metamorphic Geology, 9 (6) 723-734 doi:10.1111/j.1525-1314.1991.tb00561.x

Hillier, S., Velde, B. (1991) Octahedral occupancy and the chemical composition of diagenetic (low-temperature) chlorites. Clay Minerals, 26 (2) 149-168 doi:10.1180/claymin.1991.026.2.01

Rausell-Colom, Jose A.; Wiewióra, Andrzej; Matesanz, Emilio (1991) Relationship between composition and d₀₀₁ for chlorite. American Mineralogist, 76 (7-8). 1373-1379

Mellini, Marcello, Nieto, Fernando, Alvarez, Fernando, Gomez-Pugnaire, Maria Teresa (1991) Mica-chlorite intermixing and altered chlorite from the Nevado-Filabride micaschists, Southern Spain. European Journal of Mineralogy, 3 (1) 27-38 doi:10.1127/ejm/3/1/0027

Prieto, A. C. (1991) Structure-Composition Relationships in Trioctahedral Chlorites: A Vibrational Spectroscopy Study. Clays and Clay Minerals, 39 (5) 531-539 doi:10.1346/ccmn.1991.0390508

Hillier, S., Velde, B. (1992) Chlorite interstratified with a 7 Å mineral: an example from offshore Norway and possible implications for the interpretation of the composition of diagenetic chlorites. Clay Minerals, 27 (4) 475-486 doi:10.1180/claymin.1992.027.4.07

de Caritat, Patrice, Hutcheon, Ian, Walshe, John L. (1993) Chlorite Geothermometry: A Review. Clays and Clay Minerals, 41 (2). 219-239 doi:10.1346/ccmn.1993.0410210

Del Mar Abad-Ortega, Maria, Nieto, Fernando (1995) Extension and closure of the compositional gap between Mn- and Mg-rich chlorites toward Fe-rich compositions. European Journal of Mineralogy, 7 (2) 363-368 doi:10.1127/ejm/7/2/0363

Árkai, P., Sadek Ghabrial, D. (1997) Chlorite crystallinity as an indicator of metamorphic grade of low-temperature meta-igneous rocks: a case study from the Bükk Mountains, Northeast Hungary. Clay Minerals, 32 (2) 205-222 doi:10.1180/claymin.1997.032.2.04

Nieto, Fernando (1997) Chemical composition of metapelitic chlorites: X-ray diffraction and optical property approach. European Journal of Mineralogy, 9 (4) 829-842 doi:10.1127/ejm/9/4/0829

Li, Gejing; Peacor, Donald R.; Essene, Eric J. (1998) The Formation of Sulfides During Alteration of Biotite to Chlorite-Corrensite. Clays and Clay Minerals, 46 (6). 649-657 doi:10.1346/ccmn.1998.0460605

Lougear, A., Grodzicki, M., Bertoldi, C., Trautwein, A. X., Steiner, K., Amthauer, G. (2000) Mössbauer and molecular orbital study of chlorites. Physics and Chemistry of Minerals, 27 (4) 258-269 doi:10.1007/s002690050255

Bertoldi, C., Benisek, A., Cemic✓, L., Dachs, E. (2001) The heat capacity of two natural chlorite group minerals derived from differential scanning calorimetry. Physics and Chemistry of Minerals, 28 (5) 332-336 doi:10.1007/s002690100157

Aja, Stephen U. (2002) The stability of Fe-Mg chlorites in hydrothermal solutions: II. Thermodynamic properties. Clays and Clay Minerals, 50 (5). 591-600 doi:10.1346/000986002320679323

Zazzi, Åsa; Hirsch, Tomas K.; Leonova, Ekaterina; Kaikkonen, Andrei; Grins, Jekabs; Annersten, Hans; Edén, Mattias (2006) Structural investigations of natural and synthetic chlorite minerals by X-ray diffraction, Mössbauer spectroscopy and solid-state nuclear magnetic resonance. Clays and Clay Minerals, 54 (2). 252-265 doi:10.1346/ccmn.2006.0540210

www.zeno.org (2012) http://www.zeno.org/Meyers-1905/A/Chlor%C4%ABt

Bourdelle, Franck, Cathelineau, Michel (2015) Low-temperature chlorite geothermometry: a graphical representation based on a T–R2+–Si diagram. European Journal of Mineralogy, 27 (5). 617-626 doi:10.1127/ejm/2015/0027-2467

Aja, Stephen, Omotoso, Oladipo, Bertoldi, Christian, Dachs, Edgar, Benisek, Artur (2015) The Structure and Thermochemistry of Three Fe-Mg Chlorites. Clays and Clay Minerals, 63 (5) 351-367 doi:10.1346/ccmn.2015.0630502

Dubacq, Benoît, Forshaw, Jacob B. (2024) The composition of metapelitic biotite, white mica, and chlorite: a review with implications for solid-solution models. European Journal of Mineralogy, 36 (4). 657-685 doi:10.5194/ejm-36-657-2024

Significant localities for Chlorite GroupHide

Showing 32 significant localities out of 22,262 recorded on mindat.org.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the

symbol to view information about a locality. The

symbol next to localities in the list can be used to jump to that position on the map.

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Locality ListHide

- This locality has map coordinates listed.

- This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality.

- Good crystals or important locality for species.

- World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). ~~Struck out~~ - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.


Australia
Queensland Mareeba Shire Mungana ⓘ Red Dome Mine	[Baileychlore] AM 73 (1988) +1 other reference

Czech Republic
Central Bohemian Region Kutná Hora District Kutná Hora ⓘ Kaňk	[Orthochamosite] Am Min 43 (1958)

Germany
Baden-Württemberg Stuttgart Region Esslingen Plochingen Lützelbach ⓘ Knollenberg Keuper formation	[Sudoite] von Engelhardt et al. (1962) +1 other reference

Greece
Attica East Attica Lavreotiki Agios Konstantinos (Kamariza) Mercati mines ⓘ Christiana Mine	[Baileychlore] LAPIS 2010 7/8 (Kristalldruse ad) +2 other references

Mali
Kayes Region Bafoulabé Cercle ⓘ Diakon Commune	[Clinochlore] Currier et al. (2011)

Poland
Lower Silesian Voivodeship Świdnica County ⓘ Gmina Strzegom	[Chamosite] Dana et al. (1892)
ⓘ Żółkiewka	[Chamosite] Tomas Praszkier

Russia
Krasnoyarsk Krai Enisei Range (Yenisei Ridge; Enisei Ridge) ⓘ Tatarka Range	[var: Tatarkaite] Meister A. (1910)
Murmansk Oblast Kovdorsky District Kovdor Massif ⓘ Kovdor Phlogopite mine	[Glagolevite] M. V. Seredkin et al.: Zap. Vses. Min. Obshch.:132 (1)
Perm Krai Gornozavodskii District Sarany Saranovskii Mine ⓘ Vakhrushevaite type locality	[Vakhrushevaite] Pekov et al. (2025)
Zabaykalsky Krai Krasnochikoysky District Krasnyi Chikoy Malkhan pegmatite field ⓘ Sosedka pegmatite vein	[Borocookeite] Zagorsky et al. (2003) +2 other references

South Africa
Mpumalanga Ehlanzeni District Municipality Mbombela Local Municipality Barberton ⓘ Bon Accord Ni deposit	[Nimite] Hiemstra et al. (1968) +3 other references

Sweden
Värmland County Filipstad Långban Ore District ⓘ Långban Mine	[Gonyerite] Frondel (1955) +1 other reference

Switzerland
Valais Conthey Chamoson ⓘ Haut de Cry	[Chamosite] Berthier (1820) +1 other reference

Turkey
Erzurum Province Aşkale District Kop Daglari ⓘ Kop Krom mine	[Clinochlore var: Chromium-bearing Clinochlore] Dietrich (1978) +2 other references

UK
Wales Gwynedd Aberdaron Rhiw ⓘ Benallt Mine	[Pennantite] Campbell Smith et al. (1946) +6 other references

Ukraine
Donetsk Oblast ⓘ Donetsk	[Donbassite] Lazarenko (1940)

USA
California Calaveras County Valley Springs area ⓘ Calaveras River Canyon	Jake Harper: Field work
Connecticut Fairfield County Trumbull Long Hill ⓘ Old Mine Park (Old Tungsten Mine)	[Clinochlore] Shannon (1921b) +1 other reference
ⓘ Old Mine Plaza construction site	[Clinochlore] P Cristofono collection
Middlesex County Haddam Haddam Neck ⓘ Gillette Quarry (J-J Mine; Haddam Neck Quarry)	[Cookeite] Bowman (1902) +3 other references
Portland Collins Hill Strickland pegmatite ⓘ Strickland Quarry	[Cookeite] Ralph Lieser of Pappy’s Beryl Shop +3 other references
New Haven County ⓘ Southbury	[Clinochlore] Jeremy Zolan Collection
Maine Oxford County Buckfield ⓘ Bennett Quarry	[Cookeite] King et al. (1991) +1 other reference
Hebron Mount Rubellite ⓘ Mount Rubellite Quarries	[Cookeite] USGS Bull 445 +3 other references
Paris ⓘ Mount Mica Quarry	[Cookeite] King et al. (1994) +1 other reference
Maryland Baltimore County Holbrook ⓘ Harris Mine	[Clinochlore var: Chromium-bearing Clinochlore] Stuart Herring Collection
New Hampshire Coos County Gorham ⓘ Mascot Mine	[Chamosite] A. Plante collection +3 other references
New Jersey Sussex County Franklin ⓘ Franklin Mine	[Franklinfurnaceite] Dunn et al. (1987) +1 other reference
New York Putnam County Town of Southeast ⓘ Tilly Foster Iron Mine	[Clinochlore] - (Bridenbaugh, 1873) +1 other reference
Pennsylvania Chester County Westtown Township ⓘ Brinton's Quarry	[Clinochlore] Rocks & Min.: 21:22. +1 other reference