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Melanothallite

A valid IMA mineral species - grandfathered

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Photos of Melanothallite (3)Discuss Melanothallite

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Edit Melanothallite Add Synonym Edit CIF structures Clear Cache

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

Melanothallite, etc.

Second scoria cone, Northern Breakthrough, Great Fissure eruption, Tolbachik Volcanic field, Milkovsky District, Kamchatka Krai, Russia

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About MelanothalliteHide

Formula:

Cu₂Cl₂O

Colour:

Black, bluish black

Lustre:

Vitreous

Specific Gravity:

4.08 (Calculated)

Crystal System:

Orthorhombic

Name:

From the Greek for "black" and a "young shoot," for the mineral’s property of turning green on exposure.

Type Locality:

ⓘ Mount Vesuvius, Metropolitan City of Naples, Campania, Italy

This page provides mineralogical data about Melanothallite.

Unique IdentifiersHide

Mindat ID:

2623

Long-form identifier:

mindat:1:1:2623:5

IMA Classification of MelanothalliteHide

IMA status:

Approved, 'Grandfathered' (first described prior to 1959)

IMA Formula:

Cu²⁺₂OCl₂

First published:

1870

Type description reference:

Scacchi, A. (1870) Dell'eriocalco e del melanotallo, nuove specie di minerali. Rendiconto dell'Accademia delle Scienze Fisiche e Matematiche (sezione della Societa reale di Napoli): 9: 86-89.

Classification of MelanothalliteHide

Strunz-mindat (2026):

3.DA.05

3 : HALIDES
D : Oxyhalides, hydroxyhalides and related double halides
A : With Cu, etc., without Pb

Dana 8th ed.:

10.4.4.1

10 : OXYHALIDES AND HYDROXYHALIDES
4 : A₂(O,OH)X_q

Hey's CIM Ref.:

8.2.7

8 : Halides - Fluorides, Chlorides, Bromides and Iodides; also Fluoborates and Fluosilicates
2 : Halides of Cu

Mineral SymbolsHide

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

Symbol	Source	Reference for Standard
Mlth	IMA–CNMNC	Warr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of MelanothalliteHide

Lustre:

Vitreous

Transparency:

Opaque

Colour:

Black, bluish black

Comment:

Changes to green colours upon exposure.

Tenacity:

Brittle

Cleavage:

Perfect
One direction, perfect, probably prismatic

Density:

4.08 g/cm³ (Calculated)

Optical Data of MelanothalliteHide

Type:

Biaxial

Comments:

Deep brown in transmitted light.

Chemistry of MelanothalliteHide

Mindat Formula:

Cu₂Cl₂O

Element Weights:

Element	% weight
Cu	59.390 %
Cl	33.134 %
O	7.476 %

Calculated from ideal end-member formula.

Elements listed:

Cl, Cu, O - search for minerals with similar chemistry

Crystallography of MelanothalliteHide

Crystal System:

Orthorhombic

Class (H-M):

mmm(2/m2/m2/m) - Dipyramidal

Space Group:

Fddd

Setting:

Fddd

Cell Parameters:

a = 9.595(3) Å, b = 9.693(3) Å, c = 7.461(3) Å

Ratio:

a:b:c = 0.99 : 1 : 0.77

Unit Cell V:

693.91 Å³ (Calculated from Unit Cell)

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	Link	Year	Locality	Pressure (GPa)	Temp (K)
0005787	Melanothallite	Krivovichev S V, Filatov S K, Burns P C (2002) The cuprite-like framework of OCu4 tetrahedra in the crystal structure of synthetic melanothallite, Cu2OCl2, and its negative thermal expansion The Canadian Mineralogist 40 1185-1190		2002	synthetic	0	293

CIF Raw Data - click here to close

data_global
_chemical_name_mineral 'Melanothallite'
loop_
_publ_author_name
'Krivovichev S V'
'Filatov S K'
'Burns P C'
_journal_name_full 'The Canadian Mineralogist'
_journal_volume 40 
_journal_year 2002
_journal_page_first 1185
_journal_page_last 1190
_publ_section_title
;
 The cuprite-like framework of OCu4 tetrahedra in the crystal structure
 of synthetic melanothallite, Cu2OCl2, and its negative thermal expansion
;
_database_code_amcsd 0005787
_chemical_compound_source 'Synthetic'
_chemical_formula_sum 'Cu2 Cl2 O'
_cell_length_a 7.4691
_cell_length_b 9.5969
_cell_length_c 9.700
_cell_angle_alpha 90
_cell_angle_beta 90
_cell_angle_gamma 90
_cell_volume 695.298
_exptl_crystal_density_diffrn      4.089
_symmetry_space_group_name_H-M 'F d d d'
loop_
_space_group_symop_operation_xyz
  'x,y,z'
  'x,1/2+y,1/2+z'
  '1/2+x,y,1/2+z'
  '1/2+x,1/2+y,z'
  '3/4+x,-y,3/4+z'
  '3/4+x,1/2-y,1/4+z'
  '1/4+x,-y,1/4+z'
  '1/4+x,1/2-y,3/4+z'
  '3/4-x,y,3/4-z'
  '3/4-x,1/2+y,1/4-z'
  '1/4-x,y,1/4-z'
  '1/4-x,1/2+y,3/4-z'
  '-x,3/4+y,3/4+z'
  '-x,1/4+y,1/4+z'
  '1/2-x,3/4+y,1/4+z'
  '1/2-x,1/4+y,3/4+z'
  'x,3/4-y,3/4-z'
  'x,1/4-y,1/4-z'
  '1/2+x,3/4-y,1/4-z'
  '1/2+x,1/4-y,3/4-z'
  '3/4+x,3/4+y,-z'
  '3/4+x,1/4+y,1/2-z'
  '1/4+x,3/4+y,1/2-z'
  '1/4+x,1/4+y,-z'
  '3/4-x,3/4-y,z'
  '3/4-x,1/4-y,1/2+z'
  '1/4-x,3/4-y,1/2+z'
  '1/4-x,1/4-y,z'
  '-x,-y,-z'
  '-x,1/2-y,1/2-z'
  '1/2-x,-y,1/2-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_U_iso_or_equiv
Cu   0.00000   0.00000   0.50000   0.01400
Cl   0.12500   0.12500   0.32431   0.02130
O   0.12500   0.12500   0.62500   0.01270
loop_
_atom_site_aniso_label
_atom_site_aniso_U_11
_atom_site_aniso_U_22
_atom_site_aniso_U_33
_atom_site_aniso_U_12
_atom_site_aniso_U_13
_atom_site_aniso_U_23
Cu 0.01790 0.01300 0.01100 -0.00260 -0.00080 -0.00060
Cl 0.02890 0.02200 0.01310 -0.00870 0.00000 0.00000
O 0.01670 0.01190 0.00940 0.00000 0.00000 0.00000

X-Ray Powder DiffractionHide

Powder Diffraction Data:

d-spacing	Intensity
5.041 Å	(100)
2.518 Å	(77)
2.947 Å	(44)
2.422 Å	(20)
2.176 Å	(19)
2.816 Å	(17)
1.928 Å	(16)

Geological EnvironmentHide

Paragenetic Mode(s):

Paragenetic Mode	Earliest Age (Ga)
Stage 7: Great Oxidation Event	<2.4
45b : [Other oxidized fumarolic minerals]

Type Occurrence of MelanothalliteHide

Type Locality:

ⓘ Mount Vesuvius, Metropolitan City of Naples, Campania, Italy

General Appearance of Type Material:

Platy or scaly, to 1 cm.

Place of Conservation of Type Material:

n.d.

Geological Setting of Type Material:

Fumaroles.

Associated Minerals at Type Locality:

Reference:

Scacchi, A. (1870) Dell'eriocalco e del melanotallo, nuove specie di minerali. Rendiconto dell'Accademia delle Scienze Fisiche e Matematiche (sezione della Societa reale di Napoli): 9: 86-89.

Synonyms of MelanothalliteHide

Melanotallo

Melanothallite (of Scacchi)

Other Language Names for MelanothalliteHide

Dutch:Melanothalliet

German:Melanothallit

Russian:Меланоталлит

Spanish:Melanothallita

Common AssociatesHide

Associations Based on Photo Data:

5 photos of Melanothallite associated with Euchlorine	KNaCu₃(SO₄)₃O
5 photos of Melanothallite associated with Klyuchevskite	K₃Cu₃(Fe³⁺,Al)(SO₄)₄O₂
2 photos of Melanothallite associated with Chloromenite	Cu₉(SeO₃)₄O₂Cl₆

Related Minerals - Strunz-mindat Grouping Hide

3.DA.	Parahibbingite	Fe₂(OH)₃Cl	Trig. 3m(32/m) : R3m
3.DA.	Centennialite	CaCu₃Cl₂(OH)₆ · nH₂O (n ~ 0.7)	Trig. 3m(32/m) : P3m1
3.DA.	Bounahasite	Cu⁺Cu²⁺₂(OH)₃Cl₂	Mon. 2/m
3.DA.	Muonionalustaite	Ni₃(OH)₄Cl₂ · 4H₂O	Mon. 2/m : B2/m
3.DA.10c	Haydeeite	Cu₃Mg(OH)₆Cl₂	Trig. 3m(32/m) : P3m1
3.DA.10b	Clinoatacamite	Cu₂(OH)₃Cl	Mon. 2/m
3.DA.10c	Paratacamite	Cu₃(Cu,Zn)(OH)₆Cl₂	Trig. 3 : R3
3.DA.10c	Kapellasite	Cu₃Zn(OH)₆Cl₂	Trig. 3m(32/m) : P3m1
3.DA.10c	Leverettite	Cu₃Co(OH)₆Cl₂	Trig. 3 : R3
3.DA.10a	Hibbingite	Fe²⁺₂(OH)₃Cl	Orth. mmm(2/m2/m2/m) : Pnma
3.DA.10c	Paratacamite-(Ni)	Cu₃(Ni,Cu)(OH)₆Cl₂	Trig. 3 : R3
3.DA.10a	Kempite	Mn²⁺₂(OH)₃Cl	Orth. mmm(2/m2/m2/m) : Pnma
3.DA.10c	Tondiite	Cu₃Mg(OH)₆Cl₂	Trig. 3m(32/m) : R3m
3.DA.10a	Atacamite	Cu₂(OH)₃Cl	Orth. mmm(2/m2/m2/m) : Pnma
3.DA.10b	Belloite	Cu(OH)Cl	Mon. 2/m : P2₁/b
3.DA.10c	Misakiite	Cu₃Mn(OH)₆Cl₂	Trig. 3m(32/m) : P3m1
3.DA.10b	Iyoite	MnCuCl(OH)₃	Mon. 2/m : P2₁/m
3.DA.10c	Kuliginite	Fe₃Mg(OH)₆Cl₂	Trig. 3 : R3
3.DA.10c	Gillardite	Cu₃Ni(OH)₆Cl₂	Trig. 3m(32/m) : R3m
3.DA.10b	'Unnamed (Cu-Zn Chloride Hydroxide)'	CuZnCl(OH)₃	Mon. 2/m : P2₁/m
3.DA.10b	Botallackite	Cu₂(OH)₃Cl	Mon. 2/m : P2₁/m
3.DA.10c	Herbertsmithite	Cu₃Zn(OH)₆Cl₂	Trig. 3m(32/m) : R3m
3.DA.15	Claringbullite	Cu₄ClF(OH)₆	Hex. 6/mmm(6/m2/m2/m) : P6₃/mmc
3.DA.15	Barlowite	Cu₄BrF(OH)₆	Hex. 6/mmm(6/m2/m2/m) : P6₃/mmc
3.DA.20	Simonkolleite	Zn₅Cl₂(OH)₈ · H₂O	Trig. 3m(32/m) : P3m1
3.DA.25	Buttgenbachite	Cu₁₉(NO₃)₂(OH)₃₂Cl₄ · 2H₂O	Hex. 6/mmm(6/m2/m2/m) : P6₃/mmc
3.DA.25	Connellite	Cu₁₉(SO₄)(OH)₃₂Cl₄ · 3H₂O	Hex. 6m2 : P62c
3.DA.30	Abhurite	Sn₂₁Cl₁₆(OH)₁₄O₆	Trig. 32 : R32
3.DA.35	Ponomarevite	K₄Cu₄Cl₁₀O	Mon. 2/m : B2/b
3.DA.40	Calumetite	CaCu₄(OH)₈Cl₂ · 3.5H₂O	Orth. mmm(2/m2/m2/m) : Cmcm
3.DA.40	Anthonyite	Cu(OH,Cl)₂ · 3H₂O	Mon. 2/m
3.DA.45	Khaidarkanite	Cu₄Al₃(OH)₁₄F₃ · 2H₂O	Mon. 2/m : B2/m
3.DA.50	Bobkingite	Cu₅Cl₂(OH)₈ · 2H₂O	Mon. 2/m : B2/m
3.DA.55	Avdoninite	K₂Cu₅(OH)₄Cl₈ · H₂O	Mon. 2/m : P2₁/b
3.DA.60	Droninoite	Ni₆Fe³⁺₂(OH)₁₆Cl₂ · 4H₂O	Trig. 3m(32/m) : R3m
3.DA.70	Chrysothallite	K₆Cu₆Tl³⁺Cl₁₇(OH)₄ · H₂O	Tet. 4/mmm(4/m2/m2/m) : I4/mmm
3.DA.70	Dioskouriite	CaCu₄Cl₆(OH)₄ · 4H₂O	Mon. 2/m : P2₁/b
3.DA.75	Feodosiyite	Cu₁₁Mg₂Cl₁₈(OH)₈ · 16H₂O	Mon. 2/m : P2₁/b
3.DA.80	Romanorlovite	K₈Cu₆Cl₁₇(OH)₃	Tet. 4/mmm(4/m2/m2/m) : I4/mmm

Other InformationHide

Notes:

Soluble in water. Changes to a green, more highly hydrated substance (hydromelanothallite) upon exposure.

Health Risks:

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

Internet Links for MelanothalliteHide

mindat.org URL:

https://www.mindat.org/min-2623.html
Please feel free to link to this page.

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External Links:

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Look for Melanothallite on Mineralien Atlas

Raman and XRD data at RRUFF project

References and PDF downloads at RRUFF project

American Mineralogist Crystal Structure Database

Handbook of Mineralogy page PDF

Mineral Dealers:

Buy from D. Joyce minerals

References for MelanothalliteHide

Reference List:

Scacchi, A. (1870) Dell'eriocalco e del melanotallo, nuove specie di minerali. Rendiconto dell'Accademia delle Scienze Fisiche e Matematiche (sezione della Societa reale di Napoli): 9: 86-89.

Scacchi, A. (1884) Reale Accademia delle Scienze Fisiche e Matematiche, Naples, Rend.: 10: 158.

Zambonini, Ferruccio (1935) Mineralogia Vesuviana. second edition with Quercigh, 463 pp., Naples: 111-112.

Palache, Charles; Berman, Harry; Frondel, Clifford (1951) The System of Mineralogy (7th ed.) Vol. 2 - Halides, Nitrates, Borates, Carbonates, Sulfates, Phosphates, Arsenates, Tungstates, Molybdates, Etc. John Wiley and Sons.

Bergasova, L.P., Filatov, S.K. (1982) The chemical formula and crystallochemical characteristics of melanothallite, Cu2OCl2. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva, 111(5), 562-565.

Dunn, P. J.; Cabri, L. J.; Clark, A. M.; Fleischer, M. (1983) New mineral names. American Mineralogist, 68 (7-8). 849-852

Krivovichev, S. V., Filatov, S. K., Burns, P. C. (2002) The cuprite-like framework of OCu4 tetrahedra in the crystal structure of synthetic melanothallite, Cu2OCl2, and its negative thermal expansion. The Canadian Mineralogist, 40 (4). 1185-1190 doi:10.2113/gscanmin.40.4.1185

(2005) Melanothallite. Handbook of Mineralogy. Mineralogical Society of America

Localities for MelanothalliteHide

Showing 8 localities.

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.

Hide all sections | Show all sections

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.


Chile
Antofagasta Tocopilla Province Tocopilla ⓘ Angélica Mine	Zambra et al. (2007)

Iran
Sistan and Baluchestan Province Iranshahr County Bazman Volcano ⓘ Chahnaly deposit (Chahnali prospect)	Ali Sholeh et al. (2016)

Italy (TL)
Campania Metropolitan City of Naples ⓘ Mount Vesuvius (TL)	Palache et al. (1951)
ⓘ Vesuvius fumaroles	Pelloux (1927) +1 other reference

Russia
Kamchatka Krai Milkovsky District Tolbachik Volcanic field Great Fissure eruption (Main Fracture) Northern Breakthrough (North Breach) ⓘ First scoria cone	Pekov (1998)
ⓘ Second scoria cone	Pekov et al. (2013)
ⓘ Novaya fumarole	Pekov (1998)
ⓘ Yadovitaya fumarole	Chukanov et al. (2007)

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Melanothallite

About MelanothalliteHide

Unique IdentifiersHide

IMA Classification of MelanothalliteHide

Classification of MelanothalliteHide

Mineral SymbolsHide

Physical Properties of MelanothalliteHide

Optical Data of MelanothalliteHide

Chemistry of MelanothalliteHide

Crystallography of MelanothalliteHide

Crystal StructureHide

X-Ray Powder DiffractionHide

Geological EnvironmentHide

Type Occurrence of MelanothalliteHide

Synonyms of MelanothalliteHide

Other Language Names for MelanothalliteHide

Common AssociatesHide

Related Minerals - Strunz-mindat GroupingHide

Other InformationHide

Internet Links for MelanothalliteHide

References for MelanothalliteHide

Localities for MelanothalliteHide

Locality ListHide

Related Minerals - Strunz-mindat Grouping Hide