Atlasovit

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Atlasovit
General and classification
other names

IMA 1986-029

chemical formula
  • Cu 2+ 6 Fe 3+ Bi 3+ O 4 (SO 4 ) 5 · KCl
  • KCu 2+ 6 Fe 3+ Bi 3+ [O 4 | Cl | (SO 4 ) 5 ]
  • KCu 6 Fe 3+ [Cl | Bi 3+ O 4 | (SO 4 ) 5 ]
Mineral class
(and possibly department) 		Sulphates (selenates, tellurates, chromates, molybdates and tungstates)
System no. to Strunz
and to Dana 		7.BC.20
01/30/17/02
Crystallographic Data
Crystal system tetragonal
Crystal class ; symbol ditetragonal-dipyramidal; 4 / m  2 / m  2 / m
Space group P 4 / ncc (No. 130)Template: room group / 130
Lattice parameters a  = 9.86  Å ; c  = 20.58 Å
Formula units Z  = 4
Frequent crystal faces {001}, {110}, {012}, {014}
Physical Properties
Mohs hardness 2 to 2.5
Density (g / cm 3 ) measured: 4.20 (5); calculated: 4.12
Cleavage completely after {001}
colour dark brown
Line color light brown
transparency transparent
shine Glass gloss
radioactivity hardly detectable
Crystal optics
Refractive indices n ω  = 1.783
n ε  = 1.776
Birefringence δ = 0.007
Optical character uniaxial negative
Pleochroism Visible: ω = red-brown; ε = light yellow

Atlasovit is a very rarely occurring mineral from the mineral class of "sulfates (including selenates, tellurates, chromates, molybdates and tungstates)" with the chemical composition Cu 2+ 6 Fe 3+ Bi 3+ O 4 (SO 4 ) 5 · KCl or in the crystal-chemical structural formula notation KCu 6 Fe 3+ [Cl | Bi 3+ O 4 | (SO 4 ) 5 ]. Atlasovit is thus a potassium - copper - iron - sulfate with additional chlorine - and bismuth .

Atlasovit crystallizes in the tetragonal crystal system and develops tabular crystals with an octagonal cross-section up to about one millimeter in size. Since the mineral forms a gapless, isomorphic mixed crystal row with the related nabokoite , the two typically also grow together closely.

The transparent Atlasovit crystals are dark brown in color and their surfaces have a glass-like sheen . The streak color of the idiochromatic (self-colored) mineral is light brown.

Etymology and history

Name giver Vladimir Atlasov

The mineral was named after the Russian explorer Vladimir Vasilyevich Atlasov , who was the first to explore the Kamchatka Peninsula.

Atlasovit was discovered together with Nabokoit in mineral samples from the volcano Tolbachik , more precisely in the sublimates of the central Fumarolenfeldes on the south side of the second cone slag. After the mineral was recognized by the International Mineralogical Association (IMA) in 1986, the first description VI Popova, VA Popov, NS Rudashevskiy, SF Glavatskikh, VO Polyakov, AF Bushmakin was published in the following year.

The type material of the mineral is in the Fersman Museum in Moscow (Russia) with an unknown collection no. kept.

classification

Since the Atlasovit was only recognized as an independent mineral in 1986, it is not yet included in the 8th edition of the Strunz mineral classification, which has been outdated since 1977 . Only in the Lapis mineral directory , which was revised and updated in 2018 by Stefan Weiß, which is still based on this classic system from Karl Hugo Strunz out of consideration for private collectors and institutional collections , the mineral received the system and mineral number. VI / B.07-20 . In the "Lapis system" this corresponds to the class of "sulfates, chromates, molybdates and tungstates" and there the section "Anhydrous sulfates, with foreign anions ", where Atlasovit forms an independent but unnamed group together with Nabokoite .

The 9th edition of Strunz's mineral systematics, which has been valid since 2001 and updated by the International Mineralogical Association (IMA) until 2009, also classifies Atlasovit in the category of "Sulphates (selenates etc.) with additional anions, without H 2 O". This is, however, further subdivided according to the relative size of the cations involved , so that the mineral can be found according to its composition in the sub-section “With medium-sized and large cations”, where the “Nabokoite group” with the system no. 7.BC.20 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns Atlasovit to the class of "sulfates, chromates and molybdates" (including selenates, tellurates, selenites, tellurites and sulfites) and there in the category of "anhydrous sulfates with hydroxyl or Halogen ”. Here it can be found in the unnamed group 01/30/17 within the subsection “Anhydrous sulfates with hydroxyl or halogen and (AB) m (XO 4 ) p Z q , with m: p> 2: 1”.

Chemism

An average of four electron beam microanalyses in three different laboratories using different standards showed an average chemical composition of 30.48% Cu , 0.82% Zn , 2.04% Pb , 1.03% Te , 4.38% Fe , 11.50 % Bi , 3.20% K , 0.46% V , 0.01% Cs , 12.90% S , 2.92% Cl and 30.26% O (all data in% by weight).

On the basis of a total of 25 O and Cl ions, the empirical formula with (Cu 5.90 Zn 0.15 ) Σ = 6.05 (Fe 0.97 V 0.11 ) Σ = 1.08 (Bi 0 , 68 Pb 0.12 Te 0.10 ) Σ = 0.90 (SO 4 ) 4.95 O 4.19 · K 1.01 Cl 1.01 , to the Cu 6 Fe 3+ Bi 3+ O 4 ( SO 4 ) 5 · KCl was idealized.

Crystal structure

Atlasovit crystallizes tetragonally in the space group P 4 / ncc (space group no. 130) with the lattice parameters a  = 9.86  Å and c  = 20.58 Å as well as 4 formula units per unit cell . Template: room group / 130

Education and Locations

So far, Atlasovit could only be discovered as a sublimation product on volcanic fumaroles . As Begleitminerale can do as well Nabokoit among other Alarsit , Anglesite , Atacamit , Chalkocyanit , Chloroxiphit , Dolerophanit , Euchlorin , Fedotovit , hematite , Klyuchevskit , Lammerit , langbeinite , Piypit and Tenorite occur.

The mineral discoveries during the great fissure eruption 1975 and 1976 and the volcano on the second cinder Tolbachik in Russia are the world's only known so far (as of 2019).

See also

literature

  • В. И. Попова, В. А. Попов, Н. С. Рудашевский, С. Ф. Главатских, В. О. Поляков, А. Ф. Бушмакин: Набокоит Cu 7 TeO 4 (SO 4 ) 5 KCl и Атласовит Cu 6 Fe 3+ Bi 3+ O 4 (SO 4 ) 5 KCl - Новьіе Минеральі Вулканических эксий . In: Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva . tape 116 , no. 3 , 1987, pp. 358–367 (Russian, rruff.info [PDF; 695 kB ; accessed on November 6, 2019] with a brief English description; English transliteration: VI Popova, VA Popov, NS Rudashevskiy, SF Glavatskikh, VO Polyakov, AF Bushmakin: Nabokoite Cu 7 TeO 4 (SO 4 ) 5 KCl and atlasovite Cu 6 Fe 3+ Bi 3+ O 4 (SO 4 ) 5 · KCl. New minerals of volcanic exhalations. ).
  • John Leslie Jambor , Kenneth W. Bladh, T. Scott Ercit, Joel D. Grice, Edward S. Grew: New mineral names . In: American Mineralogist . tape 73 , 1988, pp. 927–935 (English, rruff.info [PDF; 900 kB ; accessed on November 6, 2019]).
  • Igor V. Pekov: Minerals first discovered on the territory of the former Soviet Union . 1st edition. Ocean Pictures, Moscow 1998, ISBN 5-900395-16-2 , pp. 30-31 .

Web links

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: September 2019. (PDF 2672 kB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, September 2019, accessed November 6, 2019 .
  2. ↑ a b Stefan Weiß: The large 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 c d 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.  374 (English).
  4. ↑ a b c d e Atlasovite . 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; 68  kB ; accessed on November 6, 2019]).
  5. ↑ David Barthelmy: Atlasovit MineralData. In: webmineral.com. Retrieved November 6, 2019 .
  6. ↑ a b c d Atlasovit. In: mindat.org. Hudson Institute of Mineralogy, accessed November 6, 2019 .
  7. ↑ Catalog of Type Mineral Specimens - A. (PDF 85 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed November 6, 2019 .
  8. ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1703 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed October 6, 2019 .
  9. ^ A b John Leslie Jambor , Kenneth W. Bladh, T. Scott Ercit, Joel D. Grice, Edward S. Grew: New mineral names . In: American Mineralogist . tape  73 , 1988, pp. 927–935 (English, rruff.info [PDF; 900 kB ; accessed on November 6, 2019]).
  10. ↑ Find location list for Atlasovit in the Mineralienatlas and Mindat , accessed on November 6, 2019.