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Okruschite

A valid IMA mineral species
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09435510017272007511186.jpg
Okruschite

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
08253270017272472422685.jpg
Okruschite, etc.

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
06825870017272007541084.jpg
Okruschite

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
09435510017272007511186.jpg
Okruschite

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
08253270017272472422685.jpg
Okruschite, etc.

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
06825870017272007541084.jpg
Okruschite

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
09435510017272007511186.jpg
Okruschite

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
08253270017272472422685.jpg
Okruschite, etc.

Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
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About OkruschiteHide

09051880017847187332635.jpg
Martin Okrusch
Formula:
Ca2Mn2+5Be4(AsO4)6(OH)4 · 6H2O
Colour:
White
Lustre:
Vitreous
Specific Gravity:
3.33
Crystal System:
Monoclinic
Name:
Named after Professor Martin Okrusch (3 December 1934 in Guben - ), University of Wuerzburg, Würzburg, Germany.
The arsenate analogue of roscherite. Unique combination of elements.


Unique IdentifiersHide

Mindat ID:
46010
Long-form identifier:
mindat:1:1:46010:1

IMA Classification of OkruschiteHide

IMA status:
Approved
IMA Formula:
Ca2Mn2+5Be4(As5+O4)6(OH)4·6H2O
Approval year:
2013
First published:
2014

Classification of OkruschiteHide

Strunz-mindat (2026):
8.DA.10

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
A : With small (and occasionally larger) cations

Mineral SymbolsHide

As of 2021 there are now IMA–CNMNC approved mineral symbols (abbreviations) for each mineral species, useful for tables and diagrams.

SymbolSourceReference for Standard
OkrIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43

Physical Properties of OkruschiteHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
White
Comment:
Semitransparent
Streak:
White
Cleavage:
Distinct/Good
Distinct on (010).
Parting:
Parting on (100).
Density:
3.33(2) g/cm3 (Measured)    3.340 g/cm3 (Calculated)

Optical Data of OkruschiteHide

Type:
Biaxial (-)
RI values:
nα = 1.671(3) nβ = 1.682(2) nγ = 1.687(3)
2V:
Measured: 65° (5)
Max. Birefringence:
δ = 0.016
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. Each grain retains its interference colour (retardation) while its brightness falls to black at extinction and reaches a maximum between extinction positions.

Surface Relief:
Moderate
Dispersion:
Dispersion Weak, r > v.
Optical Extinction:
X = b.

Chemistry of OkruschiteHide

Mindat Formula:
Ca2Mn2+5Be4(AsO4)6(OH)4 · 6H2O
Element Weights:
Element% weight
O38.841 %
As32.097 %
Mn19.613 %
Ca5.723 %
Be2.574 %
H1.152 %

Calculated from ideal end-member formula.
Elements listed:
As, Be, Ca, H, Mn, O - search for minerals with similar chemistry

Crystallography of OkruschiteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/b
Setting:
C2/c
Cell Parameters:
a = 16.33(4) Å, b = 12.03(3) Å, c = 6.93(1) Å
β = 94.84(5)°
Ratio:
a:b:c = 1.357 : 1 : 0.576
Unit Cell V:
1357 ų
Z:
2
Morphology:
Blocky, thick-tabular crystals consisting of curved and differently oriented laths. Forms include {010} (major), {100}, {001}, and probably {110}.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
9.68 Å(39)
4.95 Å(34)
4.17 Å(34)
3.25 Å(100)
3.11 Å(32)
2.841 Å(27)
2.711 Å(26)
1.726 Å(26)
Locality:
Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
Comments:
Fuchs Quarry, Bavaria, Germany. Data from the type description.

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
47a : [Near-surface hydration of prior minerals]
47d : [Arsenates, antimonates, selenates, bismuthinates]

Type Occurrence of OkruschiteHide

Type Locality:
ⓘ Fuchs Quarry, Hartkoppe, Sailauf, Aschaffenburg District, Lower Franconia, Bavaria, Germany
General Appearance of Type Material:
Tabular aggregates up to 0.15 × 0.3 × 0.3 mm in size of curved and somewhat misaligned laths.
Place of Conservation of Type Material:
Type material is deposited in the collections of the Fersman Mineralogical Museum of the Russian Academy of Sciences, Moscow, Russia, registration number 4434/1
Geological Setting of Type Material:
In a hydrothermal vein cross-cutting rhyolite.
Associated Minerals at Type Locality:
ArseniosideriteBraunite

Synonyms of OkruschiteHide

Other Language Names for OkruschiteHide

German:Okruschit

Relationship of Okruschite to other SpeciesHide

Member of:
Roscherite Group
Other Members of Roscherite Group:
AtencioiteCa2Fe2+3Mg2Be4(PO4)6(OH)4 · 6H2OTric. 1 : P1
FootemineiteCa2Mn2+Mn2+2Mn2+2Be4(PO4)6(OH)4 · 6H2OTric. 1 : P1
GreifensteiniteCa2Fe2+5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b
GuimarãesiteCa2Be4Zn5(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b
RoscheriteCa2Mn2+5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/m
RuifrancoiteCa2(◻,Mn)2(Fe3+,Mn,Mg)4Be4(PO4)6(OH)4(OH,H2O)2 · 4H2OMon. 2/m : B2/b
ZanazziiteCa2Mg5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b

Common AssociatesHide

Associations Based on Photo Data:
2 photos of Okruschite associated with ArseniosideriteCa2Fe3+3(AsO4)3O2 · 3H2O
1 photo of Okruschite associated with CalciteCaCO3

Related Minerals - Strunz-mindat GroupingHide

8.DA.05BearsiteBe2(AsO4)(OH) · 4H2OMon.
8.DA.05MoraesiteBe2(PO4)(OH) · 4H2OMon. m : Bb
8.DA.10ZanazziiteCa2Mg5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b
8.DA.10AtencioiteCa2Fe2+3Mg2Be4(PO4)6(OH)4 · 6H2OTric. 1 : P1
8.DA.10GuimarãesiteCa2Be4Zn5(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b
8.DA.10FootemineiteCa2Mn2+Mn2+2Mn2+2Be4(PO4)6(OH)4 · 6H2OTric. 1 : P1
8.DA.10GreifensteiniteCa2Fe2+5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/b
8.DA.10RoscheriteCa2Mn2+5Be4(PO4)6(OH)4 · 6H2OMon. 2/m : B2/m
8.DA.10RuifrancoiteCa2(◻,Mn)2(Fe3+,Mn,Mg)4Be4(PO4)6(OH)4(OH,H2O)2 · 4H2OMon. 2/m : B2/b
8.DA.15UraloliteCa2Be4(PO4)3(OH)3 · 5H2OMon. 2/m
8.DA.20WeinebeneiteCaBe3(PO4)2(OH)2 · 4H2OMon. m : Bb
8.DA.25TiptopiteK2(Na,Ca)2Li3Be6(PO4)6(OH)2 · H2OHex. 6 : P63
8.DA.40SpenceriteZn4(PO4)2(OH)2 · 3H2OMon. 2/m : P2/b
8.DA.45GlucineCaBe4(PO4)2(OH)4 · 0.5H2O

Other InformationHide

IR Spectrum:
The IR spectrum is unique and considered a diagnostic tool.
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 OkruschiteHide

References for OkruschiteHide

Localities for OkruschiteHide

Showing 1 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.
Germany (TL)
 
  • Bavaria
    • Lower Franconia
      • Aschaffenburg District
        • Sailauf
          • Hartkoppe
Williams et al. (2013) +1 other reference
Quick NavTopAbout OkruschiteUnique IdentifiersIMA Classification Classification Mineral SymbolsPhysical Properties Optical Data Chemistry Crystallography X-Ray Powder DiffractionGeological EnvironmentType Occurrence SynonymsOther LanguagesRelationshipsCommon AssociatesStrunz-MindatOther InformationInternet Links References Localities Locality List
 
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