Bournonite
Bournonite | |
---|---|
High-gloss, partly bluish bournonite crystals on colorless to white quartz from the "Yaogangxian Mine", Yizhang , China (size: 9 cm × 6.5 cm × 6 cm) | |
General and classification | |
other names |
Wheel ore |
chemical formula | PbCu [SbS 3 ] |
Mineral class (and possibly department) |
Sulfides and sulfosalts |
System no. to Strunz and to Dana |
2.GA.50 ( 8th edition : II / D.04a) 04/03/03/02 |
Crystallographic Data | |
Crystal system | orthorhombic |
Crystal class ; symbol | orthorhombic-pyramidal; mm 2 |
Space group | Pn 2 1 m (No. 31, position 5) |
Lattice parameters | a = 8.15 Å ; b = 8.69 Å; c = 7.79 Å |
Formula units | Z = 4 |
Twinning | predominantly quadruplets in the form of a cogwheel |
Physical Properties | |
Mohs hardness | 2.5 to 3 ( VHN 100 = 176 to 205) |
Density (g / cm 3 ) | measured: 5.83; calculated: 5.84 |
Cleavage | imperfect after {010}, indistinct after {100} and {001} |
Break ; Tenacity | slightly scalloped to uneven; brittle |
colour | steel gray to iron black, tapering to a bluish tinge |
Line color | steel gray to black |
transparency | opaque |
shine | Metallic gloss to matt |
Bournonite ( Rädelerz , Spießglanzbleierz , Schwarzspießglanzerz , Wölchit ) is a common mineral from the mineral class of the sulphides and sulfosalts . It crystallizes in the orthorhombic crystal system with the chemical composition PbCu [SbS 3 ] and develops short, prismatic or tabular crystals , but also granular or massive aggregates of steel gray to black color with the same line color . Fresh samples show a strong metallic luster on the surfaces of the opaque crystals, but older samples occasionally become bluish and dull.
Etymology and history
The first by Philip Rashleigh 1797 Endellionit named mineral was as determined by Bournon 1804 by Robert Jameson renamed Bournonite. Jacques Louis de Bournon (1751-1825) was a French crystallographer and mineralogist. The mining name wheel ore arose from the frequent discovery of quadruple adhesions of bournonite crystals, which look like a gear .
Bournonite was first discovered in the "Wheal Boys Mine" (also Trewetha Mine ) near St. Endellion in the English county of Cornwall .
classification
Already in the outdated 8th edition of the mineral classification according to Strunz , the bournonite belonged to the mineral class of the "sulfides and sulfosalts" and there to the department of the "complex sulfides (sulfosalts)", where together with seligmannite he created the "seligmannite series" with the system No. II / D.04a within the "lead copper spike luster group".
In the Lapis mineral directory according to Stefan Weiß, which, out of consideration for private collectors and institutional collections, is still based on this old form of Karl Hugo Strunz's system , the mineral was given the system and mineral number. II / E.16-20 . In the “Lapis system” this corresponds to the section “Sulfosalts (S: As, Sb, Bi = x)”, where bournonite also forms an independent but unnamed group together with seligmannite (as of 2018).
The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and was updated by the International Mineralogical Association (IMA) until 2009, classifies bournonite in the category of "sulfarsenides, sulfantimonides, sulfbismutides". This is further subdivided according to the crystal structure and the possible presence of additional sulfur, so that the mineral according to its composition can be found in the subsection "Island sulfarsenides (Neso sulfarsenides) etc., without additional sulfur (S)", where together with Seligmannit and Součekit it forms the unnamed group 2.GA.50 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the bournonite to the class of "sulfides and sulfosalts" and there in the department of "sulfosalts". Here he is also in the " Seligmannite group " with the system no. 03.04.03 within the sub-section “ 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" Find.
Chemism
The idealized (theoretical) composition of bournonite (PbCu [SbS 3 ]) consists of 42.40% lead , 13.00% copper , 24.91% antimony and 19.68% sulfur .
Due to mixed crystal formation with seligmannite (CuPbAsS 3 ), a small proportion of the antimony is usually replaced ( substituted ) by arsenic in natural bournonite . Bournonite samples can also contain smaller amounts of iron and / or zinc as a foreign addition . Measured silver proportions are, however, always due to adhesions with silver carriers.
Crystal structure
Bournonite crystallizes orthorhombically in the space group Pn 2 1 m (space group no. 31, position 5) with the lattice parameters a = 8.15 Å , b = 8.69 Å and c = 7.79 Å as well as 4 formula units per unit cell .
properties
In nitric acid to dissolve Bournonite with separation of sulfur and antimony on. In front of the soldering tube , it can easily be melted into a black ball, producing antimony smoke.
Education and Locations
Bournonite forms hydrothermally in medium grade zinc , lead, and copper ore deposits . Accompanying minerals are galena , tetrahedrite , pyrite , siderite and others.
So far (as of 2011) Bournonite has been found at around 850 sites around the world. In addition to its type locality "Wheal Boys Mine", the mineral appeared in the United Kingdom (Great Britain) in several places in the English counties of Cornwall and Cumbria as well as in Wales and Scotland .
Well-known sites due to unusual bournonite finds include Machacamarca in the Bolivian Department of Potosí and Saint-Laurent-le-Minier in the French department of Gard , where crystals up to 10 cm in size were found. In the “Herodsfoot Mine” near Lanreath in Cornwall, complex twin- wheel ore over 5 cm in size were mined and crystals up to 4 cm in size were found near Příbram in the Czech Republic and in the Huancavelica region in Peru.
In Germany, bournonite was found in several places in the Black Forest in Baden-Württemberg, in Franconia and the Upper Palatinate in Bavaria, near Laubuseschbach in Central Hesse, near Clausthal and Sankt Andreasberg in Lower Saxony's Harz Mountains , at several sites in the Eifel , in Siegerland and in the Westerwald of North Rhine -Westfalen to Rhineland-Palatinate, in the Sauerland and Bergisches Land in North Rhine-Westphalia, in the Saarland community Nonnweiler , near Neudorf and Wolfsberg in Saxony-Anhalt, near Freiberg and Schneeberg in the Saxon Ore Mountains and near Gera , Greiz and Saalfeld in Thuringia.
In Austria, the mineral can be found in several regions of Carinthia , Salzburg and Styria as well as on the Eichberg near Gloggnitz in Lower Austria and in the Inn and Sill valley in Tyrol, and in Switzerland it can be found in the Ticino region of Malcantone as well as in the Binntal and the municipality Collonges VS in the canton of Valais.
Other locations are Argentina , Ethiopia , Australia , Bolivia , Brazil , Bulgaria , Chile , China , Fiji , Finland , Ghana , Greece , Greenland , Indonesia , Ireland , Italy , Japan , the Channel Island Jersey , Canada , Kazakhstan , Kyrgyzstan , Colombia , Korea , Kosovo , Croatia , Mexico , Mongolia , Namibia , New Zealand , Peru , Poland , Portugal , Romania , Russia , Sweden , Slovakia , Slovenia , Spain , South Africa , Tajikistan , Tunisia , Ukraine , Hungary , Uzbekistan , the United States of America (USA ) and Vietnam .
use
Bournonite is an important lead and copper ore and is used as a raw material for the extraction of these elements.
See also
literature
- JL Bournon : Description of a triple sulfuret, of lead, antimony and copper, from Cornwall; with some observations upon the various modes of attraction which influence the formation of mineral substances, and upon the different kinds of sulfur of copper . In: Philosophical Transactions of the Royal Society of London . tape 94 , 1804, pp. 30–62 ( rruff.info [PDF; 4.4 MB ; accessed on December 27, 2019]).
- Robert Jameson : Bournonite . In: System of Mineralogy . tape 2 , 1805, pp. 579–582 (English, rruff.info [PDF; 170 kB ; accessed on December 27, 2019]).
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 475–476 (first edition: 1891).
- Petr Korbel, Milan Novák: Mineral Encyclopedia (= Villager Nature ). Edition Dörfler im Nebel-Verlag, Eggolsheim 2002, ISBN 978-3-89555-076-8 , p. 56 .
Web links
- Mineral Atlas: Bournonite (Wiki)
- Bournonite. In: mindat.org. Hudson Institute of Mineralogy(English).
- Bournonite search results. In: rruff.info. Database of Raman spectroscopy, X-ray diffraction and chemistry of minerals (RRUFF)(English).
- American-Mineralogist-Crystal-Structure-Database - Bournonite. In: rruff.geo.arizona.edu. (English).
- Bournonite. In: geomuseum.tu-clausthal.de. GeoMuseum TU Clausthal
Individual evidence
- ↑ 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. 145 (English).
- ↑ a b c d Bournonite . 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 December 27, 2019]).
- ^ Charles Hatchett: Analysis of a Triple Sulfuret, of Lead, Antimony, and Copper, from Cornwall . In: Philosophical Transactions of the Royal Society of London . tape 94 , 1804, pp. 63–69 , doi : 10.1098 / rstl.1804.0007 , JSTOR : 107139 (English, royalsocietypublishing.org [PDF; 1,2 MB ; accessed on December 27, 2019]).
- ↑ Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties. Status 03/2018 . 7th, completely revised and supplemented edition. Weise, Munich 2018, ISBN 978-3-921656-83-9 .
- ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF 1816 kB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed December 27, 2019 .
- ^ David Barthelmy: Bournonite Mineral Data. In: webmineral.com. Retrieved December 27, 2019 .
- ^ Helmut Schrätze , Karl-Ludwig Weiner : Mineralogie. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 295-296 .
- ↑ Find location list for bournonite in the Mineralienatlas and Mindat , accessed on December 27, 2019.