Jamesonite
- Berg scale
- Federerz
- Lumpenerz
- Plumosit
- Zundererz
Jamesonite is a commonly occurring mineral from the mineral class of " sulfides and sulfosalts ". It crystallizes in the monoclinic crystal system with the chemical composition FePb4Sb6S14, ie a compound of iron, lead, antimony and sulfur, which is allocated to the sulfosalts due to their crystal structure.
Jamesonite is opaque and usually developed long, prismatic to fine noble crystals parallel to the longitudinal axis (c- axis) are striped. This form predominantly fibrous- felted or radial-, tufted mineral aggregates. Fresh samples are lead- gray to gray- black in color and have a metallic, in fibrous aggregates and silky luster. After some time in air, the mineral often runs but colorful color on iridescent. As the finest Zundererz it can also be brown translucent.
Etymology and history
His final name was Jamesonite 1825 by Wilhelm von Haidinger, who named the mineral after the English mineralogist Robert Jameson ( 1774-1854 ).
The mineral was known, however, already. Already in the records of Johann Gottlob Lehmann of 1758 a Zundererz (also mountain scale and Lumpenerz ) is mentioned from the pits and Dorothea Carolina at Clausthal. Robert Jameson described it in 1820 as gray antimony and by Friedrich Mohs it is 1824 Axotomer stibnite
As a type locality applies St. Endellion near Wadebridge in the English county of Cornwall.
Classification
In the now outdated but still in use 8th edition of the mineral classification by Strunz the Jamesonite belonged to the department of " thio ", where he led the unnamed group formed together with Benavidesit II/E.22.
The 9th edition used since 2001 and valid by the International Mineralogical Association (IMA ) of the Strunz'schen Mineral classification assigns the Jamesonite in the newly defined division of " sulfosalts with SnS as an example " a. This is also further divided according to the conditions prevailing in the interconnect metals, so that the mineral is found according to its composition in the subsection "With Cu, Ag, Fe, Sn and Pb", where it together with Benavidesit and Sakharovait named after him " Jamesonite group " with the system no. 2.HB.15 forms.
The mainly common in English-speaking classification of minerals according to Dana assigns the Jamesonite in the department of " thio ". Here he is with Benavidesit in the unnamed group 03:06:07 within the sub-division of " sulfosalts with the ratio 2.0 < z / y < 2.49, and the composition (A ) i ( A2 ) j [ Bycz ], A = to find metals, semimetals B =, C = non-metals ".
Modifications and varieties
Fine nobles varieties are called Federerz. Haidinger chose in 1845 the term Plumosit (Latin plumosus: covered with downy, feathery ).
Sakharovait ( FePb4 (Bi, Sb) 6S14 ), named after the Russian mineralogist Marina Sergeevna Sakharova ( * 1917 ), since 2006 is no longer considered as a separate mineral, but as a variety of Jamesonite.
Education and Locations
Jamesonite formed by hydrothermal processes as Nebengemengteil in lead -, iron -, and antimony-containing ore passes. Accompanying minerals occur as well as other lead sulfosalts, you still calcite, dolomite, galena, pyrite, quartz, siderite, sphalerite, rhodochrosite, stibnite, tetrahedrite.
Overall Jamesonite has so far (as of 2012) are detected at around 700 localities. Apart from its type locality St. Endellion the mineral still occurred in many other places in the county of Cornwall, in some places in the county of Cumbria, and at Tavistock in Devon and Deganwy in Wales in the United Kingdom.
In Germany, the mineral is found among others in several places in the Black Forest in Baden- Württemberg; im Fichtelgebirge and Pfaffenreuth near forest Assen in Upper Palatinate Forest in Bavaria; in the Harz Mountains of Lower Saxony to Saxony -Anhalt; in mouse Bach ( Stolberg ), Old bridge, Uentrop ( Arnsberg ) and at several points in the winning country in North Rhine -Westphalia; in Rhineland-Palatinate Westerwald; in Penig and at several points in the Ore Mountains in Saxony, and in several places in the district Greiz in Thuringia.
In Austria Jamesonite could be found especially in Carinthia ( Friesach - hut mountain, Villach ), Salzburg ( Hohe Tauern, Saalfelden ) and Styria ( Schladming Tauern ).
In Switzerland, the mineral occurred mainly in the cantons of Graubünden and Ticino.
Other localities lie among others in Argentina, Azerbaijan, Australia, Bolivia, Chile, China, Ecuador, Finland, France, Ghana, Greece, India, Italy, Japan, Kazakhstan, Kyrgyzstan, Colombia, Kosovo, Luxembourg, Malaysia, Macedonia, Mexico, Namibia, Norway, Peru, Poland, Portugal, Romania, Russia, Sweden, Slovakia, Spain, South Africa, Czech Republic, Ukraine, Hungary, Uzbekistan and the United States of America.
Crystal structure
Jamesonite crystallizes in the monoclinic space group P21 / a ( Raumgruppen-Nr. 14) with the lattice parameters a = 15.57 Å; b = 18.98 Å; c = 4.03 Å and 91.8 ° β = and 2 formula units per unit cell.
The crystal structure consists of chains when Jamesonite edge-sharing polyhedra and pBS7 Fe6 octahedra. Both of which extend parallel to the c-axis and are connected by SbS3 pyramids.