Jolliffeit

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Jolliffeit
General and classification
other names

IMA 1989-011

chemical formula
  • NiAsSe
  • (Ni, Co) AsSe
Mineral class
(and possibly department) 		Sulfides and sulfosalts
System no. to Strunz
and to Dana 		2.EB.25
02.12.03.09
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  = 5.83  Å
Formula units Z  = 4
Physical Properties
Mohs hardness > 3 (harder than Clausthalit ); 6 to 6.5
Density (g / cm 3 ) calculated: 7.10
Cleavage not defined
colour tin white
Line color black
transparency opaque (opaque)
shine Metallic luster

Jolliffeit is a very rarely occurring mineral from the mineral class of "sulfides and sulfosalts" with the idealized chemical composition NiAsSe and thus chemically a nickel - arsenic - selenide and the Se analogue of Gersdorffit . As close relatives of the sulfides, the selenides are placed in the same class.

Jolliffeit crystallizes in the cubic crystal system , but has so far only been found in the form of tiny, irregular grains up to about 240  μm in size. The mineral is in any form opaque ( opaque ) and displays on the surfaces of grains zinnweißen a metallic luster . In contrast to its surface color , its line color is black.

Etymology and history

Jolliffeit was first discovered in mineral samples from drill core FH-86-21 in the Fish Hook Bay area on the Shirley Peninsula near Lake Athabasca in the Canadian province of Saskatchewan ( 59 ° 28 ′ 0 ″  N , 108 ° 24 ′ 0 ″  W ). It was first described in 1991 by Louis J. Cabri, JH Gilles Laflamme, Andrew C. Roberts, Alan J. Criddle and Larry J. Hulbert. They named the mineral in memory of Alfred "Fred" Walton Jolliffe (1907–1988), a former geologist with the Geological Survey of Canada and professor at Queen's University in Kingston, Ontario , to honor his contributions to mineral exploration in northern Saskatchewan .

The type material of the mineral is in the collection of the Geological Survey of Canada in Ottawa under the catalog no. 65747 kept.

classification

Since Jolliffeit was only recognized as an independent mineral in 1989, it is not yet included in the 8th edition of the Strunz mineral classification, which has been outdated since 1977 .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.18-25 . 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 Jolliffeit together with cobaltite , gersdorffite , hollingworthite , Irarsit , Kalungait , Milotait , Platarsit , Tolovkit , Ullmannit and Willyamit the "Cobaltit group" formed (as 2018).

The 9th edition of Strunz's mineral systematics, valid since 2001 and updated by the International Mineralogical Association (IMA) until 2009, classifies Jolliffeit in the division of "Metal sulfides with 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 , cobaltite, Gersdorffit-P2 1 3 , Gersdorffit-Pa 3 , Gersdorffit-Pca2 1 , Hollingworthit, Irarsit, Kalungait, Krutovit , Maslovit , Mayingit , 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 Jolliffeit to the class of "sulfides and sulfosalts" and there in the department of "sulfide minerals". Here it is in the " cobaltite group (cubic or pseudocubic crystals) " with the system no. 02.12.03 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 idealized (theoretical) composition of Jolliffeit (NiAsSe), the compound consists of nickel (Ni), arsenic (As) and selenium (Se) in a molar ratio of 1: 1: 1. This corresponds to a mass fraction (% by weight) of 27 , 61% Ni, 35.24% As and 37.15% Se. Since arsenic and selenium behave like sulfur- like non - metals in the compound , they are added together and the molar ratio is given as metal: sulfur (selenium, tellurium) = 1: 2.

The electron beam microanalysis on seven Jolliffeit grains from the type locality, on the other hand, showed an average composition of 23.2% by weight Ni, 36.6% by weight As and 36.6% by weight Se as well as an additional 5.1% by weight. % Cobalt (Co) and small foreign additions of 0.09% by weight copper (Cu), 0.08% by weight S and 0.06% by weight iron (Fe). This corresponds to the empirical formula (Ni 0.83 Co 0.18 ) Σ1.01 As 1.01 (Se 0.97 S 0.01 ) 0.98 , which was idealized to NiAsSe.

Crystal structure

Jolliffeit crystallizes cubically in the space group Pa 3 (space group no. 205) with the lattice parameter a  = 5.83  Å and four formula units per unit cell . Template: room group / 205

Education and Locations

At its type locality Fish Hook Bay , Jolliffeit formed in meta- sedimentary rock in a fracture zone near a dolomite - peridotite contact. The accompanying minerals mainly included clausthalite , uraninite ( pitchblende ) and various Pb-Bi-Ag- selenides . Furthermore, solid gold and silver as well as arsenopyrite , bornite , calcite , chalcopyrite , cobaltite or gersdorffite , coffinite , dolomite , hematite , lollingite , pyrite , quartz and tiemannite were discovered in the drill core .

Except at its type locality, which is also currently the only location in Canada is the mineral found previously only in the uranium ore - deposits in the mining basin Schlema - Alberoda - Hartenstein in Saxony's Erzgebirge in Germany and close to the district Předbořice of Kovářov in the Czech písek district (As of 2020).

See also

literature

  • Louis J. Cabri, JH Gilles Laflamme, Andrew C. Roberts, Alan J. Criddle, Larry J. Hulbert: Jolliffeite and unnamed CoAsSe: two new arsenoselenides from the north shore of Lake Athabasca, Saskatchewan . In: The Canadian Mineralogist . tape 29 , 1991, pp. 411-418 (English, rruff.info [PDF; 679 kB ; accessed on July 1, 2020]).
  • John Leslie Jambor , David A. Vanko: New mineral names . In: American Mineralogist . tape 77 , 1992, pp. 446–452 (English, rruff.info [PDF; 905 kB ; accessed on July 1, 2020]).
  • Hans-Jürgen Förster, Dieter Rhede, Gerhard Tischendorf: Mineralogy of the Niederschlema - Alberoda U-Se-polymetallic deposit, Erzebirge, Germany. I. Jolliffeite, NiAsSe, the rare Se-dominant analogue of gerdorffite . In: The Canadian Mineralogist . tape 42 , 2004, p. 841–849 (English, rruff.info [PDF; 429 kB ; accessed on July 1, 2020]).
  • Aloys J. Foecker, Wolfgang Jeitschko: The atomic order of the pnictogen and chalcogen atoms in equiatomic ternary compounds TPnCh (T = Ni, Pd; Pn = P, As, Sb; Ch = S, Se, Te) . In: Journal of Solid State Chemistry . tape 162 , 2001, p. 69-78 , doi : 10.1006 / jssc.2001.9342 .

Web links

Individual evidence

  1. ↑ a b c Malcolm Back, William D. Birch, Michel Blondieau and others: The New IMA List of Minerals - A Work in Progress - Updated: July 2020. (PDF; 2.44 MB) In: cnmnc.main.jp. IMA / CNMNC, Marco Pasero, July 2020, accessed July 1, 2020 .
  2. ^ A b c 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 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 .
  4. ↑ a b c Jolliffeite . 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; 60  kB ; accessed on July 1, 2020]).
  5. ↑ Jolliffeite. In: mindat.org. Hudson Institute of Mineralogy, accessed July 1, 2020 .
  6. ^ László Horváth: Mineral Species discovered in Canada and species named after Canadians (The Canadian Mineralogist Special Publication 6) . 1st edition. Mineralogical Association of Canada, Ottawa 2003, ISBN 0-921294-40-9 , pp. 98 .
  7. ↑ a b Louis J. Cabri, JH Gilles Laflamme, Andrew C. Roberts, Alan J. Criddle, Larry J. Hulbert: Jolliffeite and unnamed CoAsSe: two new arsenoselenides from the north shore of Lake Athabasca, Saskatchewan . In: The Canadian Mineralogist . tape 29 , 1991, pp. 411-418 (English, rruff.info [PDF; 679 kB ; accessed on July 1, 2020]).
  8. ↑ Catalog of Type Mineral Specimens - J. (PDF 40 kB) In: docs.wixstatic.com. Commission on Museums (IMA), December 12, 2018, accessed July 1, 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 July 1, 2020 .
  10. ↑ John Leslie Jambor , David A. Vanko: New mineral names . In: American Mineralogist . tape  77 , 1992, pp. 446–452 (English, rruff.info [PDF; 905 kB ; accessed on July 1, 2020]).
  11. ↑ List of locations for Jolliffeit in the Mineralienatlas and Mindat , accessed on July 1, 2020.