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Unnamed (Arseniosiderite-related mineral)

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About Unnamed (Arseniosiderite-related mineral)Hide

Formula:
Ca, Fe, As, O, H
An unnamed Ca-Fe3+-arsenate visually indistinguishable from arseniosiderite. Originally described by Walenta (1998) who later suggested a close relationship to wallkilldellite-Fe (Walenta, 2006).

The X-ray powder diffraction pattern is very similar to that of 'dehydrated yukonite' (cf. Ross & Post, 1997) and that of Unnamed (Pb-Fe-As-Cl-Si-Na-O-H).
See also yukonite.

Mechanical mixtures (intergrowths) of this mineral and arseniosiderite are known (U. Kolitsch, unpubl. data).


Unique IdentifiersHide

Mindat ID:
31363
Long-form identifier:
mindat:1:1:31363:6

Optical Data of Unnamed (Arseniosiderite-related mineral)Hide

Type:
Uniaxial (-)
RI values:
nω = 1.88 nε = 1.73
Max. Birefringence:
δ = 0.150
Based on recorded range of RI values above.

Interference Colours:
The colours simulate birefringence patterns seen in thin section under crossed polars. They do not take into account mineral colouration or opacity.

Michel-Levy Bar The default colours simulate the birefringence range for a 30 µm thin-section thickness. Adjust the slider to simulate a different thickness.

Grain Simulation You can rotate the grain simulation to show how this range might look as you rotated a sample under crossed polars.

Surface Relief:
Moderate
Pleochroism:
Strong
Comments:
X(E) ~colourless
Z(O) brown

Chemistry of Unnamed (Arseniosiderite-related mineral)Hide

Mindat Formula:
Ca, Fe, As, O, H
Element Weights:
Element% weight
As39.883 %
Fe29.728 %
Ca21.335 %
O8.517 %
H0.537 %

Calculated from ideal end-member formula.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
11.76 Å(10)
5.68 Å(7)
3.28 Å(6)
2.96 Å(0.5)
2.77 Å(5)
2.56 Å(2)
1.641 Å(4)
Comments:
Additional line at 2.25 (0.5b) observed for sample from Rotenbach locality.

Common AssociatesHide

Associations Based on Photo Data:
1 photo of Unnamed (Arseniosiderite-related mineral) associated with ParasymplesiteFe2+3(AsO4)2 · 8H2O

Other InformationHide

Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

Internet Links for Unnamed (Arseniosiderite-related mineral)Hide

References for Unnamed (Arseniosiderite-related mineral)Hide

Localities for Unnamed (Arseniosiderite-related mineral)Hide

Showing 5 localities.

This map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
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Locality ListHide

- This locality has map coordinates listed. - This locality has estimated coordinates. ⓘ - Click for references and further information on this occurrence. ? - Indicates mineral may be doubtful at this locality. - Good crystals or important locality for species. - World class for species or very significant. (TL) - Type Locality for a valid mineral species. (FRL) - First Recorded Locality for everything else (eg varieties). Struck out - Mineral was erroneously reported from this locality. Faded * - Never found at this locality but inferred to have existed at some point in the past (e.g. from pseudomorphs).

All localities listed without proper references should be considered as questionable.
Austria
 
  • Upper Austria
    • Eferding District
      • Stroheim
Kolitsch et al. (2008)
Chile
 
  • Atacama
    • Copiapó Province
      • Tierra Amarilla
        • Pampa Larga mining district
Uwe Kolitsch (powder X-ray diffraction) +1 other reference
Germany
 
  • Baden-Württemberg
    • Freiburg Region
      • Breisgau-Hochschwarzwald
        • Feldberg
Walenta (1998)
        • Sulzburg
Walenta (1998)
      • Ortenaukreis
        • Oberwolfach
Draxler et al. (05/21)
 
and/or  
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