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Mineralien / Minerals / Minerales => Lexikon Diskussionen Mineralien / Encyclopedia Discussion Minerals => Thema gestartet von: Lexikon am 03 Sep 20, 22:08

Titel: Claraite
Beitrag von: Lexikon am 03 Sep 20, 22:08

Lexikonseiten Diskussion - Encyclopedia Discussions (https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineralid=768)

Claraite (https://www.mineralienatlas.de/lexikon/index.php/MineralData?mineralid=768)

Titel: Claraite
Beitrag von: Michael J Pabst am 03 Sep 20, 22:08

The Crystal Diagram for Claraite does not appear to me to be Triclinic (it looks hexagonal).

Titel: Re: Claraite
Beitrag von: guefz am 04 Sep 20, 14:38

Yes, two angles in the crystal are close to 90° but the third is quite a bit off, so that should be visible in the drawing. When you switch on the axis, the hexagonal structure is clearly visible. Stefan should delete this drawing, it is directly in the database.

Titel: Re: Claraite
Beitrag von: Uwe Kolitsch am 04 Sep 20, 16:26

The mineral is pseudohexagonal.
For details see
Biagioni, C. & Orlandi, P. (2017): Claraite, (Cu,Zn)15(AsO4)2(CO3)4(SO4)(OH)14·7H2O: redefinition and crystal structure. European Journal of Mineralogy 29, 1031-1044.
https://arpi.unipi.it/retrieve/handle/11568/895507/280441/EJM-S-17-00042.pdf

Titel: Re: Claraite
Beitrag von: guefz am 04 Sep 20, 16:30

But then it should not have the three axis of the hexagonal system in the drawing when you switch axis on.

Dann müssten die Achsen aber anders eingezeichnet sein: statt a1,a2,a3,c müsste es a,b,c sein.

Titel: Re: Claraite
Beitrag von: Uwe Kolitsch am 04 Sep 20, 16:43

Yes. The drawing is an oversimplification of the true morphology. I agree it should be deleted.