Jordanite
| Jordanite | |
|---|---|
 |
|
| General and classification | |
| chemical formula |
|
|
Mineral class (and possibly department) |
Sulfides and sulfosalts |
|
System no. to Strunz and to Dana |
2.JB.30a ( 8th edition : II / E.15) 03.03.01.01 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Room group (no.) | P 2 1 / m (No. 11) |
| Lattice parameters |
a = 8.92 Å ; b = 31.90 Å; c = 8.46 Å β = 117.8 ° |
| Formula units | Z = 2 |
| Twinning | pseudo-hexagonal twins with the mirror plane (001) |
| Physical Properties | |
| Mohs hardness | 3 (VHN 50 = 106–141) |
| Density (g / cm 3 ) | measured: 6.44; calculated: 6.38 |
| Cleavage | completely after {010}; Segregation after {001} |
| Break ; Tenacity | clamshell; brittle |
| colour | lead gray; often iridescent colored |
| Line color | black |
| transparency | opaque |
| shine | Metallic luster |
Jordanite is a rarely occurring mineral from the mineral class of the "sulfides and sulfosalts" (including sulfides, selenides, tellurides, arsenides, antimonides, bismuthides, sulfarsenites, sulfantimonites, sulfbismuthites). It crystallizes in the monoclinic crystal system with the idealized composition Pb 14 [S 5 | (AsS 3 ) 6 ], so it is a compound of lead , arsenic and sulfur , which structurally belongs to the sulfo salts .
Since jordanite forms a complete mixed crystal row with geocronite and therefore part of the arsenic is usually replaced ( substituted ) by antimony , the chemical formula is represented in many sources in the simplified mixed formula Pb 14 (As, Sb) 6 S 23 (for geokronite corresponding to Pb 14 (Sb, As) 6 S 23 ). The elements indicated in round brackets can represent each other in the formula, but are always in the same proportion to the other components of the mineral.
Jordanite is opaque in every form and develops tabular crystals and pseudo-hexagonal twins with pronounced twins. Mostly, however, it occurs in the form of grape-grape and massive or coarse mineral aggregates or crusty layers in peel panels . Fresh mineral samples are initially of a lead-gray, metallic, shiny color. In the air, however, the surfaces often become iridescent in color over time. The line color of Jordanite, on the other hand, is always black.
With a Mohs hardness of 3, jordanite is one of the medium-hard minerals that can be scratched with a copper coin , similar to the reference mineral calcite .
Etymology and history
The mineral was first discovered by Hermann Jordan (1808–1887) in the Lengenbach mine in the Binn valley in the Swiss canton of Valais and described in 1864 by Gerhard vom Rath (1830–1888), who named it Jordanite after its finder.
classification
In the outdated, but partly still in use 8th edition of the mineral classification according to Strunz , the Jordanite belonged to the mineral class of "sulfides and sulfosalts" and there to the department of "sulfosalts (S: As, Sb, Bi = x)", where it belongs together Geokronite , gratonite , lengenbachite , meneghinite and tsugaruit the group of "lead sulfosalts with As / Sb (x = 3.8-3.1)" with the system no. II / E.15 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), assigns the Jordanite to the department of “sulfosalts with PbS as a model”. This is also further subdivided according to the crystal structure , so that the mineral can be found in the sub-section “ Galena derivatives with lead (Pb)” according to its composition , where the “Jordanite group” with the system no. 2.JB.30a forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Jordanite to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here he is also together with Geokronit in the unnamed group 03.03.01 within the sub-section " Sulphosalts with the ratio 3 <z / y <4 and the composition (A + ) i (A 2+ ) j [B y C z ], A = metals, B = semi-metals, C = non-metals ”.
Education and Locations
At its type locality , the Lengenbach mine in the Swiss Binntal, jordanite was formed in metamorphic lead-arsenic deposits in dolomite . The Binntal is also known for its finds of particularly large Jordanite crystals with a diameter of up to five centimeters.
However, the mineral can also be found in sub-volcanic lead-silver deposits such as Săcărâmb (also Sacarîmb , Sãcãrâmb or Szekerembe ; formerly Nagyág ) in the Romanian region of Transylvania or in hydrothermal lead-zinc displacement deposits ( sedimentary-exhalative deposits ) Formation temperature such as at Wiesloch in Baden-Württemberg (Germany) and in the Bleischarley mine ( Orzeł Biały ) near Beuthen in Poland. Depending on the locality can be used as accompanying minerals among others Boulangerit , Dufrenoysit , Enargite , galena , Guettardit , Kirkiit , Quadratit , Seligmannit , Semseyit , sphalerite , Tennantit , Tsugaruit and Zinkenite occur.
As a rare mineral formation, jordanite could only be detected at a few sites, with around 90 sites known so far (as of 2014). In addition to its type locality Lengenbach, the mineral appeared in Switzerland at the nearby Messerbach (Mässerbach) and Reckibach as well as at Halsen near Freichi in the Binn valley and in the “La Plâtrière” quarry near Granges (Lens) near Sion in the canton of Valais.
In Germany, the mineral was found in the “Segen Gottes” mine near Wiesloch, in the “Michael” mine near Weiler and “Silbereckle” near Reichenbach near Lahr / Black Forest and in the mine on the Talberg near Heiligkreuz near Weinheim in Baden-Württemberg “Bayerland” near Pfaffenreuth in the Upper Palatinate Forest in Bavaria as well as in the “Breinigerberg” mine near Breinig and the “Diepenlinchen” and “Satisfaction” mines near Mausbach (Stolberg) in North Rhine-Westphalia.
In Austria, Jordanit was previously able to use the Haidbachgraben near Semmering in Lower Austria; near Annaberg-Lungötz , Moosegg (municipality of Scheffau) , on the Radhausberg in the Gamskarlspitzengruppe and on the Lungauer Kalkspitze in Salzburg and on the Steirische Kalkspitze in Styria.
Other minerals are located in Argentina, Australia, Bolivia, Bulgaria, China, Finland, France, Greece, Ireland, Italy, Japan, Canada, Kazakhstan, Mexico, Namibia, Norway, Peru, Poland, Russia, Sweden, the Czech Republic, Tunisia, Wales in the United Kingdom (UK) and several US states.
Jordanite could also be detected in rock samples from the East Pacific Ridge , more precisely from an undersea mountain ridge named after the Greek navigator Juan de Fuca .
Crystal structure
Jordanite crystallizes isotypically with geocronite in the monoclinic crystal system in the space group P 2 1 / m (space group no. 11) with the lattice parameters a = 8.92 Å ; b = 31.90 Å; c = 8.46 Å and β = 117.8 ° and two formula units per unit cell .
The crystal structure of jordanite is similar to that of galena , but it is deformed.
See also
literature
- G. vom Rath: Mineralogical communications. III. The Jordanite. In: Annals of Physics and Chemistry. Volume 122 (1864), pp. 371–408 ( PDF 2.33 MB ; Jordanit from p. 18)
- Tetsuzo Ito, Werner Nowacki: The crystal structure of jordanite, Pb 28 As 12 S 46 . In: Journal of Crystallography. Volume 139 (1974), pp. 161-185 ( PDF 1.13 MB )
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke , Stuttgart 1978, ISBN 3-432-82986-8 , pp. 478 (first edition: 1891).
- Hans Jürgen Rösler : Textbook of Mineralogy . 4th revised and expanded edition. German publishing house for basic industry (VEB), Leipzig 1987, ISBN 3-342-00288-3 , p. 352 .
Web links
- Mineral Atlas: Jordanite (Wiki)
- Mindat - Jordanite
- Web mineral - Jordanite
- Database-of-Raman-spectroscopy - Jordanite
- American-Mineralogist-Crystal-Structure-Database - Jordanite
Individual evidence
- ↑ a b c d e Hugo Strunz , Ernest H. Nickel: Strunz Mineralogical Tables . 9th edition. E. Schweizerbart'sche Verlagbuchhandlung (Nägele and Obermiller), Stuttgart 2001, ISBN 3-510-65188-X , p. 123 .
- ↑ a b c IMA / CNMNC List of Mineral Names; March 2014 (PDF 1.5 MB)
- ↑ a b c Jordanite , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 61.9 kB )
- ↑ Petr Korbel, Milan Novák: Mineral Encyclopedia . Nebel Verlag GmbH, Eggolsheim 2002, ISBN 3-89555-076-0 , p. 60 ( Dörfler Natur ).
- ^ Helmut Schrätze, Karl-Ludwig Weiner: Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 298 .
- ↑ Mindat - Number of localities for Jordanit
- ↑ Find location list for Jordanite in the Mineralienatlas and in Mindat
- ↑ Mindat - type locality Axial Seamount, Juan de Fuca Ridge complex, East Pacific Rise, Pacific Ocean