Bellingerite

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Bellingerite
Bellingerite-245071.jpg
Light green bellingerite crystal (almost 2 mm in size) from the Chuquicamata open cast copper mine in the northern Chilean Atacama Desert
General and classification
chemical formula Cu 3 (IO 3 ) 6 · 2H 2 O
Mineral class
(and possibly department) 		Oxides and hydroxides - iodates
System no. to Strunz
and to Dana 		4.KC.05 ( 8th edition : IV / L.02)
01/21/03/01
Crystallographic Data
Crystal system triclinic
Crystal class ; symbol triclinic pinacoidal; 1
Space group P 1 (No. 2)Template: room group / 2
Lattice parameters a  = 7.26  Å ; b  = 7.95 Å; c  = 7.86 Å,
α  = 105.1 °; β  = 92.9 °; γ  = 96.9 °
Formula units Z  = 1
Frequent crystal faces {010}, {001}, {102}, {201}, {20 1 }, {011}, {02 1 } and 20 more
Twinning after} 1 10}
Physical Properties
Mohs hardness ≈ 4
Density (g / cm 3 ) measured: 4.89 (1); calculated: 4.932
Cleavage no
Break ; Tenacity slightly mussel-like; brittle
colour light green, light bluish green
Line color very light green
transparency translucent
shine Glass gloss
Crystal optics
Refractive indices n α  = 1.890
n β  = 1.900
n γ  = 1.990
Birefringence δ = 0.100
Optical character biaxial positive
Pleochroism Visible:
X = light bluish green
Y = light
bluish green Z = blue green
Other properties
Chemical behavior slightly soluble in hot water, slightly soluble in dilute hydrochloric acid

Bellingerite is a very rare mineral from the mineral class of "oxides and hydroxides" (including V [5,6] vanadates, arsenites, antimonites, bismutites, sulfites, selenites, tellurites, iodates) with the chemical composition Cu 3 (IO 3 ) 6 · 2H 2 O and is therefore chemically seen a hydrous copper - iodate .

Bellingerite crystallizes in the triclinic crystal system and develops large-area crystals up to about two millimeters, which are stretched along the b-axis. The translucent crystals are light green to light bluish green in color and leave a very light green line on the marking board .

With a Mohs hardness of around 4, bellingerite is one of the medium-hard minerals that, like the reference mineral fluorite, can be easily scratched with a pocket knife.

Etymology and history

Bellingerite was first discovered in the Chuquicamata open-cast copper mine in the Atacama Desert (Antofagasta) in northern Chile. The mineral was scientifically described for the first time in 1940 by Harry Berman and Caleb Wroe Wolfe, who named it after the German metallurgist and general director of the Chile Exploration Company, Herman Carl Bellinger (1867-1941). He had discovered the first samples of the mineral and possibly also described them.

The type material of the mineral is at Harvard University in Cambridge (Massachusetts) in the USA under catalog no. 95026 kept.

classification

Already in the outdated but still partially in use 8th edition of the mineral classification by Strunz of Bellingerit belonged to the mineral class of "oxides and hydroxides" and where it to the Department of "Iodate" along with Salesit the unnamed group IV / L.02 formed .

The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), also classifies bellingerite in the “iodates” department. However, this is further subdivided according to the possible presence of additional anions and water of crystallization , so that the mineral is classified in the sub-section “Iodates without additional anions; with H 2 O ”can be found, where it is the only member of the unnamed group 4.KC.05 .

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns bellingerite, however, to the class of "carbonates, nitrates and borates" and there to the department of " iodates - anhydrous and hydrous ". Here he is to be found as the only member of the unnamed group 01/21/03 within the sub-section “Iodates - anhydrous and water-containing with different formulas”.


Crystal structure

Bellingerite crystallizes triclinically in the space group P 1 (space group no. 2) with the lattice parameters a  = 7.26  Å ; b  = 7.95 Å; c  = 7.86 Å; α = 105.1 °; β = 92.9 ° and γ = 96.9 ° and one formula unit per unit cell . Template: room group / 2

properties

The mineral is slightly soluble in hot water, but easily soluble in dilute hydrochloric acid

Education and Locations

Bellingerite (dark blue-green) and leightonite (light blue- green) from the Chuquicamata mine, Chile ( total size : 13.8 cm × 6.9 cm
× 4.8 cm)

Bellingerit formed secondarily as vein filling in massive quartz in porphyry copper deposits , where he in paragenesis with Leightonit and gypsum occurs.

So far (as of 2015) Bellingerite could only be discovered at its type locality Chuquicamata Mine in Chile.

See also

literature

  • Harry Berman, Caleb Wroe Wolfe: Bellingerite, a new mineral from Chuquicamata, Chile. In: American Mineralogist Volume 25 (1940), pp. 505-512 ( PDF 436.3 kB )
  • S. Ghose, C. Wan: Structural chemistry of copper and zinc minerals. II. Stereochemistry of copper (II) and iodine (V) in bellingerite, 3Cu (IO 3 ) 2 · 2H 2 O In: Acta Crystallographica Volume 30 (1974), pp. 965-974

Web links

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

Individual evidence

  1. ↑ 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.  282 .
  2. ↑ a b c d Bellingerite , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 67.5 kB )
  3. ^ Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke , Stuttgart 1978, ISBN 3-432-82986-8 (first edition: 1891).
  4. ↑ Webmineral - Bellingerite
  5. ↑ a b c d e f g Mindat - Bellingerite
  6. ↑ location list for the Bellingerit Mineralienatlas and Mindat