Claraite

[Lexikon]

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Claraite

[Michael J Pabst]

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

[guefz]

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.

[Uwe Kolitsch]

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

[guefz]

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.

[Uwe Kolitsch]

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