Sword mannite

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Sword mannite
Crosta de schwertmannita obtinguda de zona de drenatge àcid de mines prop de Corta Atalaya, Huelva, Andalusia.jpg
Schwertmannite crust from acid mining waters, Corta Atalaya, Huelva Province , Andalusia, Spain (size: 3 cm × 2 cm × 0.4 cm)
General and classification
other names

IMA 1990-006

chemical formula Fe 16 3+ [O 16 | (OH) 10 | (SO 4 ) 3 ] · 10H 2 O
Mineral class
(and possibly department) 		Sulphates and relatives (formerly: oxides and hydroxides)
System no. to Strunz
and to Dana 		7.DE.15 ( 8th edition : IV / F.06)
04/06/10/01
Similar minerals Goethite , jarosite , akaganeit , ferrihydrite
Crystallographic Data
Crystal system tetragonal
Crystal class ; symbol tetragonal-dipyramidal; 4 / m
Space group P 4 / m (No. 83)Template: room group / 83
Lattice parameters a  = 10.66  Å ; c  = 6.04 Å
Formula units Z  = 1
Physical Properties
Mohs hardness 1 to 2
Density (g / cm 3 ) calculated: 3.77 to 3.99
Cleavage Please complete!
colour brownish yellow
Line color ocher yellow
transparency translucent to opaque (opaque)
shine earthy
Other properties
Chemical behavior easily soluble in water

Schwertmannite (chemically: oxyhydroxysulphate ) is a rarely occurring mineral from the mineral class of " sulfates and relatives" (previously: oxides and hydroxides , see classification ) with the chemical composition Fe 16 3+ [O 16 | (OH) 10 | (SO 4 ) 3 ] · 10H 2 O.

Schwertmannite crystallizes in the tetragonal crystal system and usually only develops crusty coatings and earthy to coarse mineral aggregates . It also seldom develops fibrous to slightly needle-like crystals up to 100 μm in size, yellow-brown in color with ocher-yellow streak color .

Etymology and history

Schwertmannite was first discovered in 1990 in the " Pyhäsalmi Mine " near Pyhäjärvi (Oulu) in Finland and described in 1994 by Jerry Marshall Bigham, Liisa Carlson and Enver Murad, who named the mineral after Udo Schwertmann ( emeritus at the Technical University of Munich ).

Type material of the mineral is in the Natural History Museum of the University of Helsinki in Finland under catalog no. B8659 kept.

classification

In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the sword mannite belonged to the mineral class of "oxides and hydroxides" and there to the department of "hydroxides and oxidic hydrates", where together with akaganeit , boehmite , diaspore , feitknechtite , Feroxyhyt , Goethit , Groutit , Lepidokrokit , Manganit and Tsumgallit formed an independent group.

The 9th edition of Strunz's mineral systematics , which has been valid since 2001 and is used by the IMA, assigns sword mannite to the class of “sulfates (and relatives)” and there to the “sulfates (selenate, etc.) category with other anions H 2 O “a. However, this division is further subdivided according to the size of the cations and the crystal structure, so that the mineral can be found accordingly in the sub-division “with medium-sized cations, unclassified”, where it is the only member of the unnamed group 7.DE.15 .

The systematics of minerals according to Dana also assigns the sword mannite to the class of "oxides and hydroxides" and there in the department of "hydroxides and hydroxide-containing oxides". There he is the only member of the unnamed group 06.04.10 within the subdivision of "Hydroxides and hydroxide-containing oxides with various cations"

Crystal structure

Schwertmannite crystallizes tetragonally in the space group P 4 / m (space group no. 83) with the lattice parameters a  = 10.66  Å and c  = 6.04 Å as well as one formula unit per unit cell . Template: room group / 83

properties

By heating, sword mannite can be converted into hematite with Fe 2 (SO 4 ) 3 as an intermediate product.

Education and Locations

Schwertmannite arises as a secondary precipitate , which forms crusts on surfaces that have been washed over by acidic ( pH 2.5 to 4.5) mine waste water. It is believed that the formation of sword mannite is related to the activity of iron oxidizing and reducing bacteria . It occurs in paragenesis mainly with goethite, but also with jarosite , natrojarosite , ferrihydrite and other sulfides.

In addition to its type locality "Pyhäsalmi Mine" (Pyhäjärvi, Oulu) in Finland, Schwertmannite has so far (as of 2010) been found in mineral samples at the "Jeremias Glück Mine" ( Garnsdorf , Saalfeld / Saale ) and "Morassina Mine" ( Schmiedefeld ) in Germany of the Cape York meteorite found in Greenland , at the “Libiola Mine” near Sestri Levante in Italy, at the “Gunma Mine” on Honshū in Japan, in the “Wilhelm Mine” near Stara Góra in the Polish Katzbach Mountains, in several mining areas in the Slovak regions Banská Bystrica , Bratislava , Košice and Prešov , near Jáchymov and Zlaté Hory in the Czech Republic, at the “Grube Bányabérc” and the “Szent Imre Mine” in the Mátra Mountains and near Nagybörzsöny in the Börzsöny of Hungary, as well as in the US regions of Alabama , Colorado , Pennsylvania, and Tennessee .

See also

literature

  • JM Bigham, L. Carlson, E. Murad: Schwertmannite, a new iron oxyhydroxy-sulphate from Pyhasalmi, Finland, and other localities . In: Mineralogical Magazine . tape 58 , no. 4 , December 1994, ISSN  0026-461X , p. 641–648 ( arizona.edu [PDF; 537 kB ; accessed on January 21, 2019]).

Web links

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

Individual evidence

  1. ↑ a b c d e 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.  406 .
  2. ↑ David Barthelmy: Schwertmannite Mineral Data. In: webmineral.com. Retrieved January 21, 2019 .
  3. ↑ Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties . 6th, completely reworked and supplemented edition. Weise, Munich 2014, ISBN 978-3-921656-80-8 .
  4. ↑ a b c d Schwertmannite . 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; 71  kB ; accessed on January 21, 2019]).
  5. ↑ a b Schwertmannite. In: mindat.org. Hudson Institute of Mineralogy, accessed January 21, 2019 .
  6. ↑ a b JM Bigham, L. Carlson, E. Murad: Schwertmannite, a new iron oxyhydroxy-sulphate from Pyhäsalmi, Finland, and other localities . In: Mineralogical Magazine . tape 58 , no. 4 , December 1994, ISSN  0026-461X , p. 641–648 ( arizona.edu [PDF; 537 kB ; accessed on January 21, 2019]).
  7. ↑ Udo Schwertmann: Communications No. 86 Summer 1999. New mineral: Schwertmannite. In: docplayer.org. Association of Weihenstephan University Graduates, p. 6 , accessed on January 21, 2019 .
  8. ^ Simona Regenspurg, Andreas Brand, Stefan Peiffer: Formation and stability of schwertmannite in acidic mining lakes 1 . In: Geochimica et Cosmochimica Acta . tape 68 , no. 6 , March 2004, ISSN  0016-7037 , p. 1185–1197 , doi : 10.1016 / j.gca.2003.07.015 .
  9. ↑ Find location list for Schwertmannite in the Mineralienatlas and in Mindat - Schwertmannite (English)