Tulameenite

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Tulameenite
Tulameenite.jpg
Tulameenite nugget from the Tulameen River type locality , British Columbia, Canada
General and classification
other names

IMA 1972-016

chemical formula Pt 2 FeCu
Mineral class
(and possibly department) 		elements
System no. to Strunz
and to Dana 		1.AG.40 ( 8th edition : I / A.15)
02/01/04/02
Crystallographic Data
Crystal system tetragonal
Crystal class ; symbol ditetragonal-dipyramidal; 4 / m  2 / m  2 / m
Space group P 4 / mmm (No. 123)Template: room group / 123
Lattice parameters a  = 3.89  Å ; c  = 3.58 Å
Formula units Z  = 1
Physical Properties
Mohs hardness 4.5 to 5 ( VHN 50 = 420 to 456, average 442)
Density (g / cm 3 ) measured: 14.9 (synthetic); calculated: 5.62
Cleavage is missing
colour silvery white
Line color silvery white
transparency opaque (opaque)
shine Metallic luster
magnetism clearly ferromagnetic

Tulameenite a rarely occurring is mineral from the mineral class of "elements (including natural alloys, intermetallic compounds, carbides, nitrides, phosphides and silicides)" with the chemical composition Pt 2 FeCu and is thus chemically seen a natural alloy , more specifically an intermetallic compound of Platinum , iron and copper in a ratio of 2: 1: 1. Small amounts of iridium (Ir), nickel (Ni) and antimony (Sb) are also possible. With ferronickel platinum (Pt 2 FeNi) Tulameenite forms a complete solid solution series .

Tulameenite crystallizes in the tetragonal crystal system , but has so far only been discovered in the form of irregularly rounded grains and micro nuggets up to about 0.4 mm in size. The mineral is opaque in every form and shows a metallic sheen on the silver-white grain surfaces .

Etymology and history

Tulameenite was first discovered in a soap deposit on the Tulameen River , a tributary of the Similkameen River in the Canadian province of British Columbia . The mineral was analyzed and described by Louis J. Cabri, Dalton R. Owens and JH Gilles Laflamme, who named it after its type locality . Since samples from the soaps on the Similkameen River were also obtained for the analysis of the mineral, both rivers are considered type localities.

The mineral description and chosen name were submitted to the International Mineralogical Association (IMA) for examination in 1972 (internal register number 1972-016). This recognized the mineral as independent in the same year. The new discovery was published the following year in the scientific magazine The Canadian Mineralogist .

The type material of the mineral is in the Royal Ontario Museum in Toronto, Canada under the catalog no. M33256 and in the National Museum of Natural History in Washington, DC, USA under catalog no. 128460 kept.

classification

Already in the outdated but still partially in use 8th edition of the mineral classification by Strunz of Tulameenite belonged to the mineral class of "elements" and then to the Department of "metals and intermetallic alloys (semimetals)" where he collaborated with Chengdeit , ferronickel platinum , Nielsenit , Isoferroplatin and Tetra platinum Ferro the unnamed group I / A.15 formed.

The 9th edition of Strunz's mineral systematics , which has been in effect since 2001 and is used by the IMA, also classifies the tulameenite in the “Metals and Intermetallic Compounds” section. However, this is further subdivided according to the predominant metals in the compound, which have been divided into metal families according to their related properties. According to its composition, tulameenite can be found in the subdivision “ PGE metal alloys”, where the “tetraferroplatin group” with system no. Is now only found together with ferronickel platinum and tetraferroplatinum. 1.AG.40 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the Tulameenite to the class and there in the department of the same name of "elements". Here he is also the namesake together with tetraferroplatinum, ferronickelplatinum and Potarit in the " tetraferroplatinum group (space group P 4 / mmm ) " with the system no. 02/01/04 within the sub-section "Elements: Platinum Group Metals and Alloys".

Chemism

The theoretical composition of Pt 2 FeCu consists of 76.57% platinum, 10.96% iron and 12.47% copper. Natural platinum alloys, however, always contain small amounts of foreign matter. The samples examined by Cabri, Owens and Laflamme contained up to 1.99% by weight iridium, up to 3.77% nickel and up to 3.52% by weight antimony, as well as additions of ruthenium (Ru), Osmium (Os), rhodium (Rh) and palladium (Pd) are possible.

Crystal structure

Tulameenite crystallizes tetragonally in the space group P 4 / mmm (space group no. 123) with the lattice parameters a  = 3.89  Å and c  = 3.58 Å and one formula unit per unit cell . Template: room group / 123

Similar to the crystal structure of tetraferroplatinum , the structure of tulameenite consists of alternating layers with platinum or iron and copper atoms. Due to the slight differences in the atomic radii of platinum (135 pm), iron (140 pm) and copper (135 pm) and the regular arrangement of the three elements in the crystal lattice (superstructure), the structure as a whole is reduced to a tetragonal symmetry instead of one to form cubic substitution solid solution as would be expected with the cubic crystallizing starting metals.

properties

Tulameenite shows clear ferromagnetic properties and is attracted by a steel needle.

Education and Locations

Tulameenite formed in fine-grained ultramafic rocks . The accompanying minerals include chalcopyrite , chromite , geversite , magnetite and various Pt-Fe alloys.

In addition to its type locality on the Tulameen River and Similkameen River in British Columbia, the mineral has so far only been found in Canada in the Marathon deposit, which is rich in platinum group elements, in the Coldwell complex near Thunder Bay in the Canadian province of Ontario.

Other sites known so far (March 2018) are in Jerusalem Creek near Woodburn in the Australian state of New South Wales , the Cr-Pt-Pd deposit Luanga near Curionópolis (Pará) in Brazil, near Yubdo in the Ethiopian administrative region Oromia ( Oromiyaa ) , the Alto Condoto intrusion in the Municipio de Condoto of the Colombian Department del Chocó , in the Platinova Reef Kangerlussuaq Complex in Greenland, the Horokanai soap deposit near Uryugawa in the Uryū-gun district on the Japanese island of Hokkaidō , on the Chindwin River near Monywa ( Sagaing Region ) in Myanmar, in the ophiolites of the Pirogues River in the southern province of New Caledonia, on the island municipality of Leka in Norway, in the Freetown Gabbro complex in western Sierra Leone , in the Bushveld complex in the South African provinces of Limpopo and Mpumalanga and in the Kapalagulu intrusion on Lake Tanganyika in Tanzania.

A large number of finds are also known from Russia, including the Aldan Highlands in Eastern Siberia, the Kamchatka Peninsula in the Far East, Lake Onega and the Oulankajoki River in the Republic of Karelia and the Sverdlovsk Oblast in the Urals .

In the USA, tulameenite has been found on the Salmon River in the Bethel Census Area of Alaska, in the Stillwater Complex in Montana and in Chester County in Pennsylvania.

See also

literature

  • Louis J. Cabri, Dalton R. Owens, JH Gilles Laflamme: Tulameenite, a new platinum-iron-copper mineral from placers in the Tulameen River area, British Columbia . In: The Canadian Mineralogist . tape 12 , no. 1 , 1973, p. 21–25 ( rruff.info [PDF; 636 kB ; accessed on January 31, 2018]).
  • Michael Fleischer , Joseph A. Mandarino: New Mineral Names . In: American Mineralogist . tape 59 , 1974, pp. 381–384 ( minsocam.org [PDF; 467 kB ; accessed on February 1, 2018]).
  • Mohammad Shahmiri, S. Murphy, DJ Vaughan: Structural and Phase Equilibria Studies in the System Pt-Fe-Cu and the Occurrence of Tulameenite (Pt 2 FeCu) . In: Mineralogical Magazine . tape 49 , no. 353 , 1985, pp. 547–554 , doi : 10.1180 / minmag . 1985.049.353.08 .
  • Peter Bayliss: Revised unit cell dimensions, space group, and chemical formula of some metallic minerals . In: The Canadian Mineralogist . tape 28 , 1990, pp. 751-755 ( rruff.info [PDF; 436 kB ; accessed on January 31, 2018]).
  • Louis J. Cabri, Alexandr D. Genkin: Re-examination of Pt alloys from lode and placer deposits, Urals . In: The Canadian Mineralogist . tape 29 , no. 3 , 1991, pp. 419–425 ( short description at GeoScienceWorld [PDF]).
  • Andrei Y. Barkov, Robert F. Martin, Mahmud Tarkian, Glenn Poirier, Yves Thibault: Pd – Ag Tellurides from a Cl-rich environment in the Lukkulaisvaara layered intrusion, Northern Russian Karelia . In: The Canadian Mineralogist . tape 39 , no. 2 , 2001, p. 639-653 , doi : 10.2113 / gscanmin.39.2.639 .
  • Nadezhda D. Tolstykh, Eugeniy G. Sidorov, Andrey P. Kozlov: Platinum-group Minerals in Lode and Placer deposits associated with the Ural-Alaskan-Type Gal'Moenan complex, Koryak – Kamchatka platinum Belt, Russia . In: The Canadian Mineralogist . tape 42 , no. 2 , 2004, p. 619–630 , doi : 10.2113 / gscanmin.42.2.619 .

Web links

Commons : Tulameenite  - collection of images, videos and audio files

Individual evidence

  1. ↑ a b c d 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.  45 .
  2. ↑ a b David Barthelmy: Tulameenite Mineral Data. In: webmineral.com. Retrieved June 29, 2019 .
  3. ↑ a b Stefan Weiß: The large Lapis mineral directory. All minerals from A - Z and their properties . 6th completely revised and supplemented edition. Weise, Munich 2014, ISBN 978-3-921656-80-8 .
  4. ↑ a b c d e f Tulameenite . 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 January 30, 2018]).
  5. ^ A b c Louis J. Cabri, Dalton R. Owens, JH Gilles Laflamme: Tulameenite, a new platinum-iron-copper mineral from placers in the Tulameen River area, British Columbia . In: The Canadian Mineralogist . tape 12 , no. 1 , 1973, p. 21–25 ( rruff.info [PDF; 636 kB ; accessed on January 31, 2018]).
  6. ↑ Type locality Placer Deposits, Tulameen River. In: mindat.org. Hudson Institute of Mineralogy, accessed June 29, 2019 . and type locality placer deposits, Similkameen River, Princeton, Similkameen Mining Division, British Columbia, Canada. In: mindat.org. Hudson Institute of Mineralogy, accessed June 29, 2019 .
  7. ^ Friedrich Klockmann : Klockmanns textbook of mineralogy . Ed .: Paul Ramdohr , Hugo Strunz . 16th edition. Enke, Stuttgart 1978, ISBN 3-432-82986-8 , pp.  399 (first edition: 1891).
  8. ↑ a b c List of locations for tulameenite in the Mineralienatlas and Mindat ( accessed on June 29, 2019).