Baileychlor

Baileychlor
	Baileychlor ( Prullans , Catalonia )
General and classification
other names	IMA 1986-056
chemical formula	(Zn, Fe 2+ , Al, Mg) 6 [(OH) 2 \| (OH) 6 \| (Si, Al) 4 O 10 ]
Mineral class; (and possibly department)	Silicates and Germanates
System no. to Strunz ; and to Dana	9.EC.55 ( 8th edition : VIII / H.23) ; April 71, 01.06
Crystallographic Data
Crystal system	triclinic
Crystal class ; symbol	triklin-pedial; 1 or triclinic pinacoidal; 1
Space group	C 1 (No. 1, position 2) or C 1 (No. 2, position 3)
Lattice parameters	a = 5.35 Å ; b = 9.26 Å; c = 14.40 Å ; α = 90 °; β = 97.1 °; γ = 90 °
Formula units	Z = 2
Physical Properties
Mohs hardness	2.5 to 3
Density (g / cm 3 )	measured: 3.18 (2); calculated: 3.195
Cleavage	completely after {001}
colour	yellow-green to dark green, light blue, zoned
Line color	light green to white
transparency	transparent
shine	Pearlescent
Crystal optics
Refractive indices	n α = 1.582 ; n γ =
Birefringence	δ = 0.032
Optical character	biaxial

Baileychlor is a very rare mineral from the mineral class of " silicates and germanates ". It crystallizes in the triclinic crystal system with the chemical composition (Zn, Fe ²⁺ , Al, Mg) ₆ [(OH) ₂ | (OH) ₆ | (Si, Al) ₄ O ₁₀ ] and thus represents the zinc end member of the chlorite group.

Baileychlor usually develops fine-grained or fibrous mineral aggregates from yellow-green to dark-green in color with light green streak color , the surface of which shows a mother-of-pearl sheen .

Etymology and history

The mineral was named in honor of the head of the Department of Geology and Geophysics at the University of Wisconsin – Madison , Professor Sturges W. Bailey (1919–1994). The second part -chlor indicates that it is a member of the chlorite group .

Baileychlor was first discovered in 1986 in the "Red Dome Mine" near the villages of Chillagoe and Herberton in the Australian Tablelands Regional Council and described by Audrey C. Rule and Frank Radke. The International Mineralogical Association (IMA) recognized the mineral in the same year under the internal accession number IMA1986-056 .

Type material of the mineral is in the Smithsonian Institution (Register No. NMNH 164430 ), the South Australian Museum (Register No. 13592 ) and the Geological Museum of the University of Wisconsin-Madison (Register No. 6000/1 ).

classification

In the meanwhile outdated, but still in use 8th edition of the mineral systematics according to Strunz , the baileychlor belonged to the mineral class of "silicates and germanates" and there to the department of "phyllosilicates", where together with borocookite , chamosite , cookeit , donbassite , franklinfurnaceite , Gonyerit , clinochlore , Manandonit , nimite , Orthochamosit , Pennantit , sudoite the large group of chlorites formed.

The used since 2001 and valid from the IMA 9th edition of Strunz'schen systematic mineral also assigns the Baileychlor in the class of "silicates and Germanates" and then in the Department of " phyllosilicates one (phyllosilicates)". However, this section is more precisely subdivided according to the crystal structure, so that the mineral can be found according to its structure in the sub-section "Layered silicates (phyllosilicates) with mica sheets, composed of tetrahedral or octahedral networks", where it can be found together with borocookite, chamosite, cookeit, donbassite , Franklinfurnaceite, Glagolevit , Gonyerit, Klinochlor, Nimit, Orthochamosit, Pennantit and Sudoit the still existing "chlorite group" with the system no. 9.EC.55 forms.

The systematics of minerals according to Dana also assigns bailey chlorine to the class of "silicates and germanates" and there in the department of "layered silicate minerals". Here it is together with Borocookeit, Chamosit, Cookeit, Donbassit, Klinochlor, Nimit, Orthochamosit, Pennantit, Sudoit in the "Chlorite group (tri-dioctahedral)" with the system no. 71.04.01 to be found in the sub-section “ Layered Silicates: Layers of six-membered rings, alternating 1: 1, 2: 1 and octahedral ”.

Crystal structure

Baileychlor crystallizes triclinically in the space group C 1 (space group no. 1, position 2) or C 1 (no. 2, position 3) with the lattice parameters a = 5.35 Å ; b = 9.26 Å; c = 14.40 Å; α = 90 °; β = 97.1 ° and γ = 90 ° as well as 2 formula units per unit cell . Template: room group / 1.2Template: room group / 2.3

Education and Locations

Baileychlor forms at the edges of colloidal calcite - veins within highly oxidized collapses of Karst - breccias of skarns . There it occurs in paragenesis with andesine , garnets , Vesuvianite , zinc-containing chamosite , goethite , hematite , chalcosine , solid copper and malachite .

Baileychlor has so far (as of 2010) been detected at around 10 sites worldwide. In Australia, the mineral was found next to its type locality “Red Dome Mine” (Queensland) in the “Kara Mine” and in soil studies in Zeehan on Tasmania . In Austria, Baileychlor was found near Lichtenau in Gföhl (Lower Austria). In Switzerland, the mineral appeared near Lengenbach and Messerbach in the Binntal . Other locations are Argentina , Canada , Greece , Namibia and Spain .

literature

Audrey C. Rule, Frank Radke: Baileychlore, the Zn end member of the trioctahedral chlorite series . In: American Mineralogist . tape 73 , 1988, pp. 135-139 ( minsocam.org [PDF; 582 kB ; accessed on May 10, 2018]).

Web links

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

Mineral Atlas: Baileychlor (Wiki)

Individual evidence

↑ ^a ^b ^c ^d ^e 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. 673 .
↑ Webmineral - Baileychlore (English)
↑ ^a ^b ^c ^d The numbering of this axis position does not correspond to the order of the International Tables for Crystallography , because it is not listed there.
↑ ^a ^b ^c 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 .
↑ ^a ^b Baileychlore . 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; 70 kB ; accessed on May 10, 2018]).
↑ ^a ^b ^c Mindat - Baileychlore (English)

[StrunzNickel-1] 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. 673 .

[Webmineral-2] Webmineral - Baileychlore (English)

[Num_ITC_inoff-3] The numbering of this axis position does not correspond to the order of the International Tables for Crystallography , because it is not listed there.

[Lapis-4] 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 .

[Datenblatt-5] Baileychlore . 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; 70 kB ; accessed on May 10, 2018]).

[Mindat-6] Mindat - Baileychlore (English)