Haggit
| Haggit | |
|---|---|
 |
|
| General and classification | |
| chemical formula | V 3+ V 4+ O 2 (OH) 3 |
|
Mineral class (and possibly department) |
Oxides and hydroxides |
|
System no. to Strunz and to Dana |
4.HE.25 ( 8th edition : IV / G.08) 04/06/03/01 |
| Crystallographic Data | |
| Crystal system | monoclinic |
| Crystal class ; symbol | monoclinic prismatic; 2 / m |
| Room group (no.) | C 2 / m (No. 12) |
| Lattice parameters |
a = 12.17 Å ; b = 2.99 Å; c = 4.83 Å β = 98.2 ° |
| Formula units | Z = 2 |
| Physical Properties | |
| Mohs hardness | 4.5 |
| Density (g / cm 3 ) | calculated: [3.51] |
| Cleavage | is missing |
| colour | black, yellowish gray to dark gray reflection color |
| Line color | not defined |
| transparency | opaque |
| shine | weak metallic luster |
Häggit is a rarely occurring mineral from the mineral class of " oxides and hydroxides ". It crystallizes in the monoclinic crystal system with the chemical composition V 3+ V 4+ O 2 (OH) 3 and thus belongs to a special group of oxides or hydroxides, the so-called polyvanadates (V [5,6] vanadates) with a combination Vanadium with the oxidation state 3+ and 4+. Structurally, Häggit is one of the layer vanadates ( phyllovanadates ).
Häggit is opaque and only develops microscopic, needle-like or flaky crystals , which are usually connected to fibrous or kidney - shaped mineral aggregates and are found in the form of crusty coatings and crack fillings on or in other minerals. Normally, Häggit is black in color, but shows a yellowish-gray to dark-gray reflection color under the incident light microscope .
Etymology and history
Was first discovered in Häggit rock samples corresponding to a core of about 55 meters (180-181 feet ) depth of the well "TR-713" were collected, which in a sandstone - deposit . / Sec 4 SE / 4 (NE 27, T. 52 N., R 66 W.) near the town of Carlile in Crook County , Wyoming, USA . The mineral was described in 1957/58 by Howard T. Evans jr. and Mary E. Mrose, who named it after the Swedish chemist Gunnar Hägg (1903–1986).
Type material of the mineral is kept in the National Museum of Natural History in Washington, DC, USA (Catalog No. 162623).
classification
Already in the outdated, but partly still in use 8th edition of the mineral classification according to Strunz , the Häggit belonged to the mineral class of "oxides and hydroxides" and there to the department of "vanadium oxides (polyvanadates with V 4 + / 5 + )", where it belongs together Doloresit , Duttonit and Lenoblit the group of "Schichtvanadate" with the system number. IV / G.08 .
The 9th edition of Strunz's mineral systematics, which has been in effect since 2001 and is used by the International Mineralogical Association (IMA), also classifies the Häggit in the "V [5,6] -Vanadate" division. This is further subdivided according to the crystal structure , so that the mineral can be found according to its composition in the sub-section "Layer vanadates (Phyllovanadates)", where it is the only member of the unnamed group 4.HE.25 .
The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns Häggit to the class of "oxides and hydroxides" and there in the category of "hydroxides and hydroxides containing oxides". Here he is to be found as the only member of the unnamed group 04/06/03 within the sub-section “ Hydroxides and Hydroxide Oxides with Various Cations ”.
Education and Locations
Häggite forms in oxidation zones of uranium - vanadium - deposits of the Colorado plateau type. The accompanying minerals include doloresite , pyrite and genuine selenium .
As a rare mineral formation, Häggit could only be detected at a few sites, although around 20 sites are known to date (as of 2014). In addition to its type locality drill hole "TR-713" at Carlile and the nearby Carlile Mine in the northern Black Hills of Wyoming, the mineral occurred in the United States in the Paradox Valley ( Montrose County ) in Colorado, at Maggie Creek and Elko in Elko County of Nevada, in several locations in the Grants District ( McKinley County and Cibola Counties ) in New Mexico, at Edgemont ( Fall River County ) in South Dakota, and in Parco No. 23 Mine in the Thompsons District ( Grand County (Utah) Grand County ), Utah.
The only known site in Germany so far is the Red Bear pit near Sankt Andreasberg in the Upper Harz in Lower Saxony.
Other previously known sites include the Valgraveglia Mine (Gambatesa Mine) near Reppia in the Italian metropolitan city of Genoa , the Karamurun Se-U deposit on the Ili River in Kazakhstan, the Srednyaya Padma Mine on the Zaonezhie peninsula on Lake Onega in northwestern Russia and the Dzhentuar Uranium deposit in the Kyzylkum desert of Uzbekistan .
Crystal structure
Häggit crystallizes monoclinically in the space group C 2 / m (space group no. 12) with the lattice parameters a = 12.17 Å ; b = 2.99 Å; c = 4.83 Å and β = 98.2 ° and two formula units per unit cell .
See also
literature
- Howard T. Evans Jr., Mary E. Mrose: The crystal structures of three new vanadium oxide minerals. In: Acta Crystallographica. Volume 11, Part 1 (January 1958), pp. 56–58 doi : 10.1107 / S0365110X58000141 ( available online as USGS publication from 1957, PDF 316.3 kB)
- Howard T. Evans, Jr., Mary E. Mrose: A crystal chemical study of the vanadium oxide minerals, Häggite and Doloresite. In: The American Mineralogist. Volume 45, November – December 1960, pp. 1144–1166 ( PDF 1.4 MB )
- Helmut Schrätze, Karl-Ludwig Weiner: Mineralogy. A textbook on a systematic basis . de Gruyter, Berlin; New York 1981, ISBN 3-11-006823-0 , pp. 478 .
Web links
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. 260 .
- ↑ a b Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties . 5th completely revised and supplemented edition. Weise, Munich 2008, ISBN 978-3-921656-70-9 .
- ↑ a b Häggit , In: John W. Anthony, Richard A. Bideaux, Kenneth W. Bladh, Monte C. Nichols (Eds.): Handbook of Mineralogy, Mineralogical Society of America , 2001 ( PDF 97.7 kB )
- ↑ Webmineral - Häggite
- ^ Howard T. Evans, Jr., Mary E. Mrose: The crystal structures of three new vanadium oxide minerals. In: Acta Crystallographica. Volume 11, Part 1 (January 1958), pp. 56–58 doi : 10.1107 / S0365110X58000141 ( available online as USGS publication from 1957, PDF 316.3 kB)
- ↑ Mindat - Number of localities for Häggite
- ↑ Find location list for Häggit in the Mineralienatlas and in Mindat