Quenselite
| Quenselite | |
|---|---|
 |
|
| General and classification | |
| chemical formula |
|
|
Mineral class (and possibly department) |
Oxides and hydroxides |
|
System no. to Strunz and to Dana |
4.FE.30 ( 8th edition : IV / F.14) 04/06/01/02 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Room group (no.) | P 2 / a (No. 13) |
| Lattice parameters |
a = 5.61 Å ; b = 5.70 Å; c = 9.15 Å β = 93.0 ° |
| Formula units | Z = 4 |
| Frequent crystal faces | {100}, {010}, {011}, {101}, {10 3 }, {111} |
| Physical Properties | |
| Mohs hardness | 2.5 |
| Density (g / cm 3 ) | measured: 6.84; calculated: 7.133 |
| Cleavage | completely after {001} |
| Break ; Tenacity | flexible in thin leaflets |
| colour | pitch black, dark brown in transmitted light |
| Line color | dark brownish gray |
| transparency | opaque |
| shine | Metallic luster |
| Crystal optics | |
| Refractive indices | n α = 2.300 |
| Birefringence | δ = 2.300 |
| Optical character | biaxial positive |
Quenselite is a very rare mineral from the mineral class of " oxides and hydroxides ". It crystallizes in the monoclinic crystal system with the chemical composition PbMn 3+ O 2 (OH), so it is a lead - manganese oxide with additional hydroxide ions .
Quenselite is opaque in every form and develops only very small, mica-like, leafy to tabular crystals of pitch black color with a dark brownish- gray streak color and metallic sheen .
Etymology and history
Quenselite was first discovered in the "America Stollen" near Långban in Sweden and described in 1925 by Gustaf Flink , (also Gustav Flink , 1849–1931) who named the mineral after the Swedish mineralogist Percy Dudgeon Quensel (1881–1966). He was mainly concerned with the mineralogy of the Långbangpits and founded a collection of Långbang type minerals at Stockholm University . In this type collection, Quenselit has the register no. 333.
classification
In the now outdated, but still in use 8th edition of the mineral classification according to Strunz , the quenselite belonged to the mineral class of "oxides and hydroxides" and there to the department of "hydroxides and oxidic hydrates (water-containing oxides with layer structure)", where he was the only member unnamed group IV / F.14 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), classifies the quenselite in the newly defined division of "hydroxides (without V or U)". This is further subdivided according to the possible presence of hydroxide ions (OH) and / or water of crystallization (H 2 O) as well as the crystal structure, so that the mineral can be classified according to its composition and structure in the sub-section “Hydroxides with OH, without H 2 O; Layers of edge-linked octahedra "can be found where it forms together with / as the only member the unnamed group 4.FE.30 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the quenselite to the class of "oxides and hydroxides" and there in the department of "hydroxides and hydroxides containing oxides". Here it can be found together with lithiophorite in the unnamed group 06.04.01 within the sub-section “ Hydroxides and hydroxides containing various cations ”.
Education and Locations
At its type locality Långban to Quenselit formed in metamorphic changes in iron-manganese ore bodies , where he met with barite , Braunit , calcite and Hausmannite socialized occurred.
So far (as of 2013) only a few quenselite samples from a total of four locations could be found. Besides Långban in Sweden, these are still the "Shengli Pipes" of Mengyin - kimberlite field in the Chinese mountains Yimeng Shan , the "Mori Mine" in Yamagata Prefecture on the Japanese island of Honshu and the "Burgin Mine" in the eastern Tintic Mountains in Utah County in the USA.
Crystal structure
Quenselite crystallizes monoclinically in the space group P 2 / a (space group no. 13) with the lattice parameters a = 5.61 Å ; b = 5.70 Å; c = 9.15 Å and β = 93.0 ° as well as four formula units per unit cell .
See also
literature
- Gust. Fast: Quenselite, a new mineral from Långban , In: Geologiska Föreningens i Stockholm Förhandlingar. Volume 47, 1925, pp. 377-384 ( rruff.info PDF; 712 kB).
- Friedrich Klockmann : Klockmann's textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp. 557 (first edition: 1891).
Web links
- Mineral Atlas: Quenselite (Wiki)
- Database-of-Raman-spectroscopy - Quenselite.
- American-Mineralogist-Crystal-Structure-Database - Quenselite.
- Webmineral - Quenselite .
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. 240 .
- ↑ 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. 408 .
- ↑ a b c d Quenselite. 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; 69.2 kB).
- ↑ a b Mindat - Quenselite.
- ^ Project Runeberg: Nordisk familjebok - Flinder's river - Flintporslin. (Swedish)
- ^ The Mineralogical Record - Gustav Flink. (English)
- ↑ Find location list for Quenselite in the [Mineralienatlas] and in [Mindat]