Zincite
| Zincite | |
|---|---|
 (size: 5.9 × 3.8 × 1.5 cm) |
|
| General and classification | |
| other names |
|
| chemical formula | Pb 9 Sb 22 S 42 |
|
Mineral class (and possibly department) |
Sulfides and sulfosalts - sulfosalts |
|
System no. to Strunz and to Dana |
2.JB.35a ( 8th edition : II / E.26) 08/03/01/01 |
| Similar minerals | Enargite , manganite , stibnite |
| Crystallographic Data | |
| Crystal system | hexagonal |
| Crystal class ; symbol | hexagonal-pyramidal; 6th |
| Space group | P 6 3 (No. 173) |
| Lattice parameters | a = 22.12 Å ; c = 4.32 Å |
| Formula units | Z = 1 |
| Physical Properties | |
| Mohs hardness | 3 to 3.5 |
| Density (g / cm 3 ) | measured: 5.33; calculated: 5.34 |
| Cleavage | indistinct after {11 2 0} |
| Break ; Tenacity | uneven |
| colour | gray-white, steel-gray, tapering in different colors |
| Line color | steel gray to black, finely rubbed red-brown |
| transparency | opaque |
| shine | Metallic luster |
Zinkenite , also spelled Zinckenit and known under the mining name lead antimony gloss or synonymously as Keeleyite , is a mineral from the mineral class of " sulfides and sulfosalts " with the chemical composition Pb 9 Sb 22 S 42 , so it consists of lead , antimony and sulfur in proportion from 9:22:42.
Zinkenite crystallizes in the hexagonal crystal system and develops predominantly thin, prismatic and opaque crystals up to about 5 cm in length that are striped along the Z-axis , but also radial to matted or massive aggregates of white to steel-gray color and metallic luster . The stroke is usually steel gray to black in color, but changes to a reddish brown color when the sample is finely rubbed. In the open air, Zinkenit can turn colored after a while.
Etymology and history
Zinkenite was first discovered in 1825 in the Graf Jost-Christian-Zeche near Wolfsberg / Stolberg in Germany and described in 1826 by Gustav Rose , who named the mineral after its discoverer Johann Ludwig Carl Zincken (also called zinc in later publications ).
classification
Already in the outdated, but still in use 8th edition of the mineral classification according to Strunz , the zinkenite belonged to the mineral class of "sulfides and sulfosalts" and there to the department of "sulfosalts", where together with scainiite it formed the unnamed group II / E.26 .
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), classifies the zinkenite as the newly defined department of “sulfosalts with PbS as a model”. This is also further subdivided according to the crystal structure or the predominant metal in the compound, so that the mineral can be found according to its composition in the sub-section "Galena derivatives with lead (Pb)", where it is the only member of the unnamed group 2 .JB.35a forms.
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns zinkenite to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here he is the namesake of the "Zinkenit group" with the system no. 03.08.01 and the other members Pillait , Pellouxit and Tazieffit within the subdivision of “ Sulphosalts with the ratio 1 <z / y <2 and the composition (A +) i (A2 +) j [ByCz], A = metals, B = semi-metals , C = non-metals ”.
Crystal structure
Zinkenite crystallizes hexagonally in the space group P 6 3 (space group no. 173) with the lattice parameters a = 22.15 Å and c = 4.33 Å and one formula unit per unit cell .
Education and Locations
Zinkenite separates from hydrothermal solutions in various ore courses . Begleitminerale include Boulangerit , Bournonite , Jamesonit , Stannin and stibnite .
As a rather rare mineral formation, zinkenite can sometimes be abundant at various sites, but overall it is not very common. So far (as of 2017) more than 200 sites are known worldwide. In addition to its type locality Grube Jost Christian in Saxony-Anhalt, the mineral also occurred in Germany in several places in the Black Forest in Baden-Württemberg, near Brandholz in the Bavarian Fichtel Mountains , near Uentrop (Arnsberg) and Nuttlar (Meschede) in North Rhine-Westphalia, in several places the Eifel and at Raubach in Rhineland-Palatinate, at Kleinvoigtsberg ( Großschirma ) in Saxony and Greiz in Thuringia.
In Switzerland, zinkenite has so far only been found on the Felsberger Calanda, a summit of the Calenda mountain range in the canton of Graubünden.
Among other things, the Itos Mine and the San José Mine near Oruro in Bolivia became known due to their large crystal finds with a diameter of up to 5 cm, but zinkenite could also be found in other areas of the Oruro and Potosí departments .
Other locations are Argentina , Australia , China , France , Greece , Italy , Japan , Canada , Kazakhstan , Kyrgyzstan , Luxembourg , Mexico , Mongolia , Peru , Portugal , Romania , Russia , Serbia , Slovakia , Spain , Tajikistan , Czech Republic , Turkey , Ukraine , the United Kingdom (Great Britain) and the United States of America (USA).
use
Zinkenite is only mined as a raw material for lead extraction when it accumulates locally . Otherwise it is a rather insignificant ore and serves as a mineral sample for collectors and mineralogists.
See also
literature
- Petr Korbel, Milan Novák: Mineral Encyclopedia (= Villager Nature ). Nebel Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 61 .
Web links
- Mineral Atlas: Zinkenite (Wiki)
- Mindat - Zinkenite (English)
- RRUFF Database-of-Raman-spectroscopy - Zinkenite (English)
- American-Mineralogist-Crystal-Structure-Database - Zinkenite (English)
Individual evidence
- ↑ a b c d e f Piers PK Smith: Direct imaging of tunnel cations in zinkenite by high-resolution electron microscopy . In: American Mineralogist . tape 71 , 1986, pp. 200 ( rruff.info [PDF; 806 kB ; accessed on April 14, 2017]).
- ↑ Webmineral - Zinkenite (English)
- ↑ a b c American-Mineralogist-Crystal-Structure-Database - Zinkenite (English)
- ↑ a b c Zinkenite . In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America . 2001 ( handbookofmineralogy.org [PDF; 61 kB ; accessed on April 13, 2017]).
- ↑ a b Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 479-480 (first edition: 1891).
- ↑ Thomas Witzke : The discovery of Zinkenit
- ↑ Mindat - Number of localities for zinkenite
- ↑ Find location list for zinkenite in the Mineralienatlas and Mindat