Aikinit

from Wikipedia, the free encyclopedia
Aikinit
Aikinite - Berezovsk, Urals.JPG
Aikinit (steel-gray crystal needles) from Berezovsk in the Urals
General and classification
other names

Needle ore

chemical formula
  • Molecular formula : PbCuBiS 3
  • Oxide formula: 2 PbS · Cu 2 S · Bi2S 3
Mineral class
(and possibly department) 		Sulfides and sulfosalts
System no. to Strunz
and to Dana 		2.HB.05 ( 8th edition : II / E.30)
04/03/05/01
Crystallographic Data
Crystal system orthorhombic
Crystal class ; symbol orthorhombic-dipyramidal; 2 / m  2 / m  2 / m
Space group Pnma (No. 62)Template: room group / 62
Lattice parameters a  = 11.608  Å ; b  = 4.0279 Å; c  = 11.275 Å
Formula units Z  = 4
Physical Properties
Mohs hardness 2 to 2.5
Density (g / cm 3 ) measured: 7.07; calculated: 7.255
Cleavage indistinct after {010}
Break ; Tenacity uneven
colour lead-gray, red-brown to black, rarely white to cream-colored
Line color grey black
transparency opaque
shine Metallic luster

Aikinite , also known by its mining name needle ore , is a rarely occurring mineral from the mineral class of " sulfides and sulfosalts ". It crystallizes in the orthorhombic crystal system with the chemical composition PbCuBiS 3 and is therefore chemically a compound of lead , copper , bismuth and sulfur , which is assigned to the sulfosalts due to its crystal structure .

Aikinite forms shiny metallic , prismatic to needle-like crystals that are striped parallel to the c-axis , but also occurs in the form of radial and massive mineral aggregates . the opaque crystals are lead-gray, reddish-brown or black in color and leave a gray-black line on the marking board . White to cream-colored aikinites are also rarely found.

Etymology and history

Aikinite was first discovered in the " Berjosowski Gold Mine" in Russia and described in 1843 by Edward John Chapman (1821–1904), who named the mineral in honor of the author of the then well-known and popular work "A Manual of Mineralogy", Arthur Aikin ( 1773–1854), named after him, although the name Aikenit first appears in its first description .

However, the mineral appears in different sources under different synonyms. It was given the mining designation needle ore due to its frequent, needle-shaped crystal formation. This was taken over into the English Acicular ore and the name Aciculite (after Nicol, 1849), in German Aciculit, was derived from it.

In the "Mohs' mineral system" from 1853, revised by Gustav Adolf Kenngott , according to Haidinger , it is listed as patrinite (also prismatic bismuth luster and needle ore ) with the formula 3Pb, Cu 2 S, Bi 2 S 3 .

Among other things, in Thomas Egleston's “A Catalog of Minerals and Synonyms” (1892), the name Belonite, which can be traced back to Ernst Friedrich Glocker , appears as a synonym for Aikinite .

classification

In the meanwhile outdated, but still in use 8th edition of the mineral classification according to Strunz , the aikinite belonged to the mineral class of the "sulfides and sulfosalts" and there to the general department of the "sulfosalts", where together with Emilit , Friedrichit , Gladit , Hammarit , Krupkait , Lindströmmit , Paarit , Pekoit , Salzburgit and Soucekit formed an independent group.

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 assigns the aikinite to the class of "sulfides and sulfosalts" (sulfides, selenides, tellurides, arsenides, antimonides, bismuthides, sulfarsenites, Sulfantimonites, sulfbismuthites), there, however, in the more finely subdivided section of “sulfosalts with SnS as a model”. This is, however, further subdivided according to the cations involved , so that the mineral can be found according to its composition in the sub-section “With Cu , Ag , Fe , Sn and Pb ”, where it is found together with Berryite , Emilite, Friedrichite, Gladite, Hammarite , Jaskólskiit , Krupkait, Lindströmmit, Meneghinit , Paarit, Pekoit and Salzburgit the "Meneghinit series" with the system no. 2.HB.05 forms.

The systematics of minerals according to Dana also assigns the aikinit to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here is the namesake of the "Aikinit group (Orthorhombic, contains Pb, Cu, Bi, and S)" with the system no. 04/03/05 and the other members Krupkait, Gladit, Hammarit, Friedrichit, Pekoit, Lindströmit and Salzburgit within the subdivision of “Sulphosalts with the ratio 3> z / y and the composition (A + ) i (A 2+ ) j [B y C z ], A = metals, B = semi-metals, C = non-metals ”.

Education and Locations

Close up of needle-like aikinite crystals from the Kara Mine, Hampshire District , Tasmania
Grainy aikinite aggregate from Tule Canyon ( Esmeralda County ), Nevada (size: 2.9 × 1.8 × 1.1 cm)

Aikinite formed hydrothermally in ore - courses . Accompanying minerals include bismuthinite , chalcopyrite , enargite , galena , gold , pyrite , quartz and tennantite .

As a rather rare mineral formation, aikinite can sometimes be abundant at different sites, but overall it is not very common. So far (as of 2015) around 260 sites are known to be known. Particularly noteworthy due to its special mineral finds are Jida in the Russian Republic of Buryatia , where the largest aikinite crystals to date with a length of up to one meter were found, as well as the type locality Berjosowski (Sverdlovsk), which is also in Russia , where crystals up to 3 cm long were found were. Granular aggregates with a diameter of up to 5 cm were recovered from the “Outlaw Mine” in Nye County (Nevada).

In Germany, the mineral could be found in several areas of the Black Forest (Baden-Württemberg), the Odenwald (Hesse), near Bad Lauterberg in the Harz Mountains (Lower Saxony), in the Brethrenbund mine in Siegen-Eiserfeld (North Rhine-Westphalia), in the "Grube Grüneau “( Grüne Au , Grünau ) near Schutzbach (Rhineland-Palatinate) and in the Ore Mountains (Saxony).

In Austria, Aikinit was found on the Großfragant (Carinthia), in the Hohe Tauern (Salzburg) and in the Montafon (Vorarlberg). In Switzerland, the mineral has so far only been found in Val Curnera (Graubünden) and in some valleys in the canton of Valais .

Other locations include Argentina , Australia , Bolivia , Bulgaria , China , France , Greece , Greenland , Iran , Italy , Japan , Canada , Kazakhstan , Mexico , New Zealand , Nigeria , Norway , Peru , Poland , Portugal , Romania , Russia , Sweden , Serbia , Slovakia , South Africa , Tajikistan , Czech Republic , Turkey , United Kingdom (Great Britain), United States of America (USA).

Crystal structure

Aikinite crystallizes orthorhombically in the space group Pnma (space group no. 62) with the lattice parameters a  = 11.608  Å ; b  = 4.0279 Å and c  = 11.275 Å and 4 formula units per unit cell . Template: room group / 62

See also

literature

  • Edward J. Chapman: Practical Mineralogy; or, a compendium of the distinguishing characters of minerals . Hippolyte Bailliere Publisher, London 1843, p. 127 ( rruff.info [PDF; 103 kB ; accessed on August 22, 2018]).
  • Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 476 (first edition: 1891).

Web links

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

Individual evidence

  1. ↑ a b c d e Iwao Kohatsu, Bernhardt J. Wuensch: The crystal structure of aikinite, PbCuBiS 3 . In: Acta Crystallographica . B27, 1971, p. 1245-1252 , doi : 10.1107 / S0567740871003819 .
  2. ^ Helmut Schrätze , Karl-Ludwig Weiner : Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp.  296 .
  3. ↑ a b Aikinite . 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; 63  kB ; accessed on August 22, 2018]).
  4. ↑ Edward J. Chapman: Practical Mineralogy; or, a compendium of the distinguishing characters of minerals . Hippolyte Bailliere Publisher, London 1843, p. 127 ( rruff.info [PDF; 103 kB ; accessed on August 22, 2018]).
  5. ^ Mineralogical Records - Chapman, Edward John
  6. ^ A b Thomas Egleston : A Catalog of Minerals and Definitions . John Wiley & Sons, New York 1892, p.  4 ( available online at archive.org  - Internet Archive [accessed August 22, 2018]).
  7. ^ Adolf Kenngott: The Mohs'sche mineral system, according to the current standpoint of science . Carl Gerold & Sohn, Vienna 1853, p. 118 ( rruff.info [PDF; 783 kB ; accessed on August 22, 2018]).
  8. ↑ Mindat - Number of localities for Aikinit
  9. ↑ Mineral Atlas: Mineral Records
  10. ↑ a b Petr Korbel, Milan Novák: Mineral Encyclopedia (=  Dörfler Natur ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 56 .
  11. ↑ Find location list for aikinite at the Mineralienatlas and at Mindat