Mayingite

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Mayingite
General and classification
other names

IMA 1993-016

chemical formula IrBiTe
Mineral class
(and possibly department) 		Sulfides and sulfosalts
System no. to Strunz
and to Dana 		2.EB.25
02.12.01.19
Crystallographic Data
Crystal system cubic
Crystal class ; symbol cubic-disdodecahedral; 2 / m  3
Space group Pa 3 (No. 205)Template: room group / 205
Lattice parameters a  = 6.50  Å
Formula units Z  = 4
Physical Properties
Mohs hardness 4 ( VHN 50 = 158–241, ⌀ 178 kg / mm 2 )
Density (g / cm 3 ) calculated: 12.77
Cleavage is missing
Break ; Tenacity brittle
colour steel black, in incident light bright white with a yellowish tinge
Line color black
transparency opaque (opaque)
shine Metallic luster

Mayingite is a very seldom occurring mineral from the mineral class of " sulphides and sulphosalts " with the chemical composition IrBiTe and thus, chemically speaking, iridium - bismuth - telluride .

Mayingite crystallizes in the cubic crystal system and has so far only been found in the form of coarse aggregates up to about 0.2 mm in size and grown in chromite in the form of thin veins up to about 0.2 mm thick and 1 mm long. The mineral is opaque in every form and of steel black, in incident light also bright white, yellowish color with a metallic sheen on the surfaces. His stroke color is also black.

Etymology and history

Mayingite was first discovered in mineral samples from a soap on the Luan River near Maying (Chicheng) ( Chengde district ) about 230 km north-northeast of Peking ( Beijing ) in the Chinese province of Hebei . The first description was in 1995 by Zuxiang Yu , who named the mineral after its type locality .

The type material of the mineral is kept in the Chinese Geological Museum (English National Museum for Geology , NMG) in Beijing.

classification

Since Mayingite was only recognized as an independent mineral in 1993 and this was only published in 1995, it is not yet listed in the 8th edition of the Strunz mineral classification, which has been outdated since 1977 . Only 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 , was the mineral given the system and mineral number. II / D.17-155 . In the "Lapis system" this corresponds to the class of "sulfides and sulfosalts" and there the section "sulfides with [the molar ratio] metal: S, Se, Te <1: 1", where mayingite together with aurostibite , cattierite , changchengite , Dzharkenit , Erlichmanit , Fukuchilit , Geversit , Hauerit , Insizwait , Krutaite , Laurit , Maslovit , Michenerit , Padmait , Penroseite , pyrite , Sperrylith , Testibiopalladit , Trogtalit , Vaesit and Villamanínit the "pyrite group" with the system number. II / D.17 forms (as of 2018).

The 9th edition of Strunz's mineral systematics, valid since 2001 and updated by the International Mineralogical Association (IMA) until 2009, classifies Mayingite in the newly defined division of "Metal sulfides with a molar ratio of M: S ≤ 1: 2". This is further subdivided according to the exact molar ratio and the predominant metals in the compound, so that the mineral can be found in the sub-section "M: S = 1: 2, with Fe, Co, Ni, PGE etc." according to its composition where it together with Changchengit, Cobaltit , Gersdorffit-P213 , Gersdorffit-Pa3 , Gersdorffit-Pca21 , Hollingworthit , Irarsit , Jolliffeit , Kalungait , Krutovit , Maslovit, Michenerit, Milotait , Padmait, Platarsit , Testibiopalladit, Tolovkit , Ullmannit and Willyamit the " Gersdorffitgruppe "with the system no. 2.EB.25 forms.

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns mayingite to the class of "sulphides and sulphosalts" and there in the category of "sulphide minerals". Here, however, it is in the " pyrite group (isometric: Pa3) " with the system no. 02.12.01 to be found within the subsection “Sulphides - including selenides and tellurides - with the composition A m B n X p , with (m + n): p = 1: 2”.

Chemism

According to the ideal (theoretical) composition of mayingite (IrBiTe), the mineral consists of iridium (Ir), bismuth (Bi) and tellurium (Te) in a molar ratio of 1: 1: 1, which corresponds to a mass fraction (% by weight) of 36, 35% Ir, 39.52% Bi and 24.13% Te.

The analysis of 11 measurements on the type material from Maying, however, also revealed small additions between 0.3 to 3.2% (average 1.9%) platinum (Pt) and traces of up to 0.2% copper (Cu).

Crystal structure

Mayingite crystallizes cubically in the space group Pa 3 (space group no. 205) with the lattice parameter a  = 6.50  Å and 4 formula units per unit cell . Template: room group / 205

Education and Locations

Mayingite is found in chromite - ores and mineral concentrates from soap deposits , where it can occur in addition to chromite mostly in paragenesis with solid gold and platinum as well as with irarsite , iridisite , laurite , magnetite and shuanfengite .

Mayingite is one of the very rare mineral formations and has so far only been detected in a few samples from a narrowly limited area. In addition to its type locality, a river soap near Maying , the mineral was also found in mineral concentrates near Gaotai and other unnamed soap deposits on the Luan River in Chengde County, part of the Chinese province of Hebei .

See also

literature

  • Zuxiang Yu: Mayingite - A new iridium bismuthide-telluride . In: Acta Mineralogica Sinica . tape 15 , 1995, p. 5–8 (Chinese, rruff.info [PDF; 243 kB ; accessed on May 18, 2020]).
  • John Leslie Jambor , Nikolai N. Pertsev, Andrew C. Roberts: New mineral names . In: American Mineralogist . tape 81 , 1996, pp. 251 (English, rruff.info [PDF; 556 kB ; accessed on May 18, 2020]).

Web links

Individual evidence

  1. ↑ a b Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: March 2020. (PDF; 2.44 MB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, March 2020, accessed May 18, 2020 .
  2. ↑ 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.  105 (English).
  3. ↑ a b c d e Mayingite . 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; 59  kB ; accessed on May 18, 2020]).
  4. ↑ Mayingite. In: mindat.org. Hudson Institute of Mineralogy, accessed May 18, 2020 .
  5. ↑ a b 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 .
  6. ^ A b John Leslie Jambor , Nikolai N. Pertsev, Andrew C. Roberts: New mineral names . In: American Mineralogist . tape  81 , 1996, pp. 251 (English, rruff.info [PDF; 556 kB ; accessed on May 18, 2020]).
  7. ^ The Depositories of Mineral Type Specimens. (PDF 311 kB) Commission on Museums (IMA), 2002, accessed on August 29, 2019 .
  8. ↑ Catalog of Type Mineral Specimens - M. (PDF 124 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed May 18, 2020 .
  9. ↑ Ernest H. Nickel, Monte C. Nichols: IMA / CNMNC List of Minerals 2009. (PDF; 1.82 MB) In: cnmnc.main.jp. IMA / CNMNC, January 2009, accessed May 18, 2020 .
  10. ↑ Mayingite. In: Mineralienatlas Lexikon. Stefan Schorn u. a., accessed on May 18, 2020 .
  11. ↑ David Barthelmy: Mayingite Mineral Data. In: webmineral.com. Retrieved May 18, 2020 .
  12. ↑ List of localities for Mayingite in the Mineralienatlas and Mindat , accessed on May 18, 2020.