Chabournéit

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Chabournéit
Chabourneite-Wakabayashilite-89635.jpg
Chabournéit and Wakabayashilith (yellow) from the type locality Jas Roux in the Pelvoux mountain group (Hautes-Alpes), France (field of view 4 mm)
General and classification
other names

IMA 1976-042

chemical formula
  • Tl 4 Pb 2 (Sb, As) 20 S 34
  • (Tl, Pb) 5 (Sb, As) 21 S 34
  • Tl 21 (Sb, As) 91 S 147
Mineral class
(and possibly department) 		Sulfides and sulfosalts
System no. to Strunz
and to Dana 		2.HF.10
03.08.12.01
Crystallographic Data
Crystal system triclinic
Crystal class ; symbol triklin-pedial; 1
Space group P 1 (No. 1)Template: room group / 1
Lattice parameters a  = 16.346  Å ; b  = 42.602 Å; c  = 8.534 Å
α  = 95.86 °; β  = 86.91 °; γ  = 96.88 °
Formula units Z  = 1
Physical Properties
Mohs hardness 2.5 to 3 ( VHN 25 = 78 to 124, average 95 kg / mm 2 )
Density (g / cm 3 ) measured: 5.104; calculated: 5.121
Cleavage is missing
Break ; Tenacity shell-like
colour gray-black to black
Line color red-brown
transparency opaque
shine weak metallic sheen to greasy sheen

Chabournéite is a very rarely occurring mineral from the mineral class of "sulfides and sulfosalts" with the chemical composition Tl 4 Pb 2 (Sb, As) 20 S 34 . The elements antimony and arsenic indicated in round brackets can represent each other in the formula ( substitution , diadochie), but are always in the same proportion to the other components thallium and sulfur . Structurally, the mineral belongs to the sulfo salts .

Chabournéit crystallizes in the triclinic crystal system and rarely develops millimeter-sized crystals . Usually it is found closely interwoven with Pierrotite . The mineral, which is opaque in every form, is gray-black to black in color and has a faint, metal-like to fat-like sheen on the surface . In the incident Chabournéit appears white. In addition, red, internal reflections were observed along cracks. Its line color , on the other hand, is red-brown.

Etymology and history

The mineral was first discovered and described in 1974 by Joseph Mantienne as part of his doctoral thesis on thallium mineralization by Jas Roux in the French department of Hautes-Alpes . According to Mantienne's research, it was the most common Thallifer phase in Jas Roux. He named the newly discovered mineral after the “Chabournéou” glacier , at the foot of which it was found. According to his brief description, chabournéit occurs there in matt black aggregates or crusts and macroscopically indistinguishable from pierrotite and clinopierrotite. Chabournéit is always associated with réalgar and very often with stibnite, more rarely with smithite, routhierite, laffittite and wakabayashilite.

An initial analysis of the composition and crystal structure of Chabournéit was carried out in 1979 by Antun Nagl from the Laboratory of General and Inorganic Chemistry at the University of Zagreb (Yugoslavia), who at the time worked in the Department of Crystallography and Structural Science at the University of Bern (Switzerland). The detailed description of the mineral necessary for the recognition of the mineral by the International Mineralogical Association (IMA) follows in 1981 by Zdenek Johan , Joseph Mantienne and Paul Picot .

The type material of the mineral is kept in the mineralogical collection of the Mines ParisTech (also Ecole Nationale Supérieure des Mines or English National School of Mines ).

classification

Since the Chabournéit was only recognized as an independent mineral in 1976 and this was only published in 1979, it is not yet listed in the 8th edition of the Strunz mineral classification, which has been out of date since 1977 . Only in the Lapis mineral directory according to Stefan Weiß, which, out of consideration for private collectors and institutional collections, is still based on this old form of Karl Hugo Strunz's system , was the mineral given the system and mineral number. II / E.14-50 . In the "Lapis system" this corresponds to the class of "sulfides and sulfosalts" and there the section "sulfosalts (S: As, Sb, Bi = x)", whereby sulfosalts are predominant in groups E.10 to E.14 Thallium / mercury and x = 4.0 to 1.6 are classified. Chabournéit forms here together with Bernardit , Boscardinit , Dalnegroit , Gabrielit , Gillulyit , Imhofit , Jankovicit , Parapierrotit , Philrothit , Pierrotit , Protochabournéit and Rebulit an independent but unnamed group (status 2018).

The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and was updated by the IMA until 2009, classifies the Chabournéit in the newly defined section of "Sulphosalts with SnS as a model". This is further subdivided according to the predominant metals or the crystal structure and the mineral according to its structure can be found in the sub-section “With SnS and PbS archetype structural units ”, where it is the only member of the unnamed group 2.HF .10 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Chabournéit to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here he is the only member of the unnamed group 08/03/12 within the subdivision “ Sulphonic salts with the ratio 1 <z / y <2 and the composition (A + ) i (A 2+ ) j [B y C z ], A = Metals, B = semi-metals, C = non-metals ”.

Chemism

The chemical composition of Chabournéit was given by Nagl in 1979 as Tl 8 Pb 4 Sb 21 As 19 S 68 for a b / 2 sub-cell. Johan, Mantienne and Picot, however, considered this composition questionable. Their microprobe analyzes on five samples each from the type locality Jas Roux in France and Abuta in Japan had a mass fraction (% by weight) of 12.81 to 23.87% thallium (Tl), 0.0 to 18.72% lead (Pb ), 25.88 to 32.92% antimony (Sb), 14.83 to 17.72% arsenic (As) and 24.73 to 26.05% sulfur (S), which corresponds to the empirical formula Tl 21-x Pb 2x (Sb, As) 91-x S 1.47 corresponds to a value for x = 0 to 17.15. In addition, the results indicated a mixed crystal formation in which Tl + and (Sb, As) 3+ can be replaced (substituted) by two Pb 2+ diadons .

Johan, Mantienne and Picot therefore proposed the formula Tl 21 (Sb, As) 91 S 147 for the lead-free end link in their mineral description published in 1981 . This formula, however, showed a significant excess of sulfur, which was not compatible with the modular organization of the crystal structure .

In order to redefine the definition and nomenclature of sulfosalts, a “sulfosalt subcommittee” was formed within the “Commission for Ore Mineralogy”, which in its 2008 report published the general formula for with Tl 5-x Pb 2x (Sb, As) 21- x S 34 indicates. The lead-free end link with x = 0 receives the formula Tl 5 (Sb, As) 21 S 34 , while Chabournéit as the lead-rich end link with x ≈ 1 receives the formula Tl 4 Pb 2 (Sb, As) 20 S 34 , which closely follows based on the formula established by Nagl.

Crystal structure

Chabournéite crystallizes triclinically in the space group P 1 (space group no. 1) with the lattice parameters a  = 16.346  Å ; b  = 42.602 Å; c  = 8.534 Å; α = 95.86 °; β = 86.91 ° ​​and γ = 96.88 ° and one formula unit per unit cell . Template: room group / 1

Education and Locations

Chabournéit formed hydrothermally in dolomitic limestones , mostly with other arsenic-thallium minerals associated as among other Pierrotit , Parapierrotit and Routhierit occurs. At its type locality , the deposit Jas Roux in Pelvoux -Gebirgsgruppe in the French municipality La Chapelle-en-Valgaudémar beside it found Aktashit , Andorit , orpiment , Laffittit , Madocit , pyrite , realgar , Smithit , sphalerite , stibnite , Twinnit , Wakabayashilith and Zinkenite as further accompanying minerals.

Chabournéit is one of the very rare mineral formations that has been detected in only a few samples from five documented sites worldwide (as of 2020). Its type locality Jas Roux is the only site in France so far.

The only known site in Switzerland so far is the Lengenbach mine, famous for its great variety of minerals, in the Binn valley, which belongs to the canton of Valais .

Other well-known sites are the former iron mine Miniera di Monte Arsiccio near Sant'Anna di Stazzema in Italy; the "Tohya" mine near Takarada in the Japanese district of Abuta-gun on Hokkaidō , where Chabournéit was associated with sphalerite and barite and getchellite ; and the Vorontsovskoye gold ore deposit near Krasnoturjinsk ( Turjinsk ) in the Russian Oblast of Sverdlovsk (Urals).

See also

literature

  • A. Nagl: The crystal structure of a thallium sulfosalt, Tl 8 Pb 4 Sb 21 As 19 S 68 . In: Journal of Crystallography . tape 150 , 1979, pp. 85–106 (English, rruff.info [PDF; 870 kB ; accessed on June 14, 2020]).
  • Zdenek Johan, Joseph Mantienne, Paul Picot: La chabournéite, un nouveau minéral thallifère . In: Bulletin de Minéralogie . tape 104 , 1981, pp. 10–15 (French, rruff.info [PDF; 487 kB ; accessed on June 14, 2020]).
  • Michael Fleischer , Louis J. Cabri, GY Chao, JA Mandarino, Adolf Pabst : New mineral names . In: American Mineralogist . tape 67 , 1982, pp. 621–624 (English, rruff.info [PDF; 817 kB ; accessed on June 14, 2020]).
  • Yves Moëlo, Emil Makovicky, Nadejda N. Mozgova, John L. Jambor, Nigel Cook, Allan Pring, Werner Paar, Ernest H. Nickel, Stephan Graeser, Sven Karup-Møller, Tonči Balic-Žunic, William G. Mumme, Filippo Vurro , Dan Topa, Luca Bindi, Klaus Bente, Masaaki Shimizu: Sulfosalt systematics: a review. Report of the sulfosalt sub-committee of the IMA Commission on Ore Mineralogy . In: European Journal of Mineralogy . tape 20 , no. 1 , 2008, p. 7–46 , doi : 10.1127 / 0935-1221 / 2008 / 0020-1778 (English, ima-mineralogy.org [PDF; 1.7 MB ; accessed on June 15, 2020]).

Web links

Commons : Chabournéite  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: March 2020. (PDF; 2.44 MB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, March 2020, accessed June 14, 2020 .
  2. ↑ a b c d e Stefan Weiss: The great Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
  3. ^ A b Hugo Strunz , Ernest H. Nickel : Strunz Mineralogical Tables. Chemical-structural Mineral Classification System . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p.  138 (English).
  4. ^ David Barthelmy: Chabournéite Mineral Data. In: webmineral.com. Retrieved June 14, 2020 (English).
  5. ↑ a b c d Zdenek Johan, Joseph Mantienne, Paul Picot: La chabournéite, un nouveau minéral thallifère . In: Bulletin de Minéralogie . tape 104 , 1981, pp. 10–15 (French, rruff.info [PDF; 487 kB ; accessed on June 14, 2020]).
  6. ↑ a b c d e Chabournéite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 (English, handbookofmineralogy.org [PDF; 64  kB ; accessed on June 14, 2020]).
  7. ↑ Joseph Mantienne: La mineralization thallifère de Jas Roux (Hautes-Alpes) -Alpes françaises . Université Pierre et Marie Curie, Paris VI May 20, 1974, p. 58 (French, pdfs.semanticscholar.org [accessed June 15, 2020] Thèse présenté pour obtenir le titre de Docteur de L'Université de Paris (mention Sciences)).
  8. ↑ full name of Antun Nagl in the publication Crystal and Molecular Structure of Two (Phenylsulfonyl) -3- (hexahydroazepin-1-yl) -ureas In: Croatica Chemica Acta , Vol. 56 No. 1, 1983. In: hrcak.srce.hr. Retrieved June 15, 2020 .
  9. ↑ A. Nagl: The crystal structure of a thallium sulfosalt, Tl 8 Pb 4 Sb 21 As 19 S 68 . In: Journal of Crystallography . tape 150 , 1979, pp. 85–106 (English, rruff.info [PDF; 870 kB ; accessed on June 14, 2020]).
  10. ↑ Catalog of Type Mineral Specimens - C. (PDF 131 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed June 14, 2020 .
  11. ↑ Ernest H. Nickel , Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF; 1.82 MB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed June 14, 2020 .
  12. ↑ Michael Fleischer , Louis J. Cabri, GY Chao, JA Mandarino, Adolf Pabst : New mineral names . In: American Mineralogist . tape  67 , 1982, pp. 621–624 (English, rruff.info [PDF; 817 kB ; accessed on June 14, 2020]).
  13. ↑ Yves Moëlo, Emil Makovicky, Nadejda N. Mozgova, John L. Jambor, Nigel Cook, Allan Pring, Werner Paar, Ernest H. Nickel, Stephan Graeser, Sven Karup-Møller, Tonči Balic-Žunic, William G. Mumme, Filippo Vurro, Dan Topa, Luca Bindi, Klaus Bente, Masaaki Shimizu: Sulfosalt systematics: a review. Report of the sulfosalt sub-committee of the IMA Commission on Ore Mineralogy . In: European Journal of Mineralogy . tape 20 , no. 1 , 2008, p. 7–46 , doi : 10.1127 / 0935-1221 / 2008 / 0020-1778 (English, ima-mineralogy.org [PDF; 1.7 MB ; accessed on June 15, 2020] Chabournéite see p. 23).
  14. ↑ a b List of locations for Chabournéit from the Mineralienatlas and Mindat , accessed on June 14, 2020.