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Ferristrunzite

A valid IMA mineral species
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07578150017271923076263.jpg
Ferristrunzite, etc.

Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
00385220017271923108041.jpg
Ferristrunzite, etc.

B224 Road cut, Aprath castle, Wuppertal, Düsseldorf, North Rhine-Westphalia, Germany
03107770017271923147380.jpg
Ferristrunzite, etc.

Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
07578150017271923076263.jpg
Ferristrunzite, etc.

Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
00385220017271923108041.jpg
Ferristrunzite, etc.

B224 Road cut, Aprath castle, Wuppertal, Düsseldorf, North Rhine-Westphalia, Germany
03107770017271923147380.jpg
Ferristrunzite, etc.

Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
07578150017271923076263.jpg
Ferristrunzite, etc.

Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
06111700017271923169192.jpg
Ferristrunzite, etc.

B224 Road cut, Aprath castle, Wuppertal, Düsseldorf, North Rhine-Westphalia, Germany
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About FerristrunziteHide

Formula:
Fe3+Fe3+2(PO4)2(OH)3 · 5H2O
Colour:
Pale yellow to creamy white, tan to very light brown
Lustre:
Sub-Vitreous, Resinous, Waxy, Silky, Dull
Hardness:
4
Specific Gravity:
2.38 - 2.50
Crystal System:
Triclinic
Member of:
Strunzite Group
Name:
Named in 1987 by Donald R. Peacor, Pete J. Dunn, William B. Simmons, and Robert A. Ramik for its chemical relationship to strunzite.


Not to be confused with ferrostrunzite (which contains both di- and trivalent Fe).


Unique IdentifiersHide

Mindat ID:
1500
Long-form identifier:
mindat:1:1:1500:0

Similar NamesHide

FerrostrunziteA valid IMA mineral speciesFe2+Fe23+(PO4)2(OH)2 · 6H2O

IMA Classification of FerristrunziteHide

Classification of FerristrunziteHide

Strunz-mindat (2026):
8.DC.25

8 : PHOSPHATES, ARSENATES, VANADATES
D : Phosphates, etc. with additional anions, with H2O
C : With only medium-sized cations, (OH, etc.):RO4 = 1:1 and < 2:1
Dana 8th ed.:
42.11.9.3

42 : HYDRATED PHOSPHATES, ETC.CONTAINING HYDROXYL OR HALOGEN
11 : (AB)3(XO4)2Zq·xH2O
Hey's CIM Ref.:
19.13.8

19 : Phosphates
13 : Phosphates of Fe alone

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

Pronunciation of FerristrunziteHide

Pronunciation:
PlayRecorded byCountry
Jolyon RalphUnited Kingdom

Physical Properties of FerristrunziteHide

Lustre:
Sub-Vitreous, Resinous, Waxy, Silky, Dull
Transparency:
Transparent, Translucent
Colour:
Pale yellow to creamy white, tan to very light brown
Streak:
Very pale yellow
Hardness:
4 on Mohs scale
Tenacity:
Brittle
Cleavage:
Distinct/Good
One, probable, parallel X-Z
Fracture:
Splintery
Density:
2.38 - 2.50 g/cm3 (Measured)    2.55 g/cm3 (Calculated)

Optical Data of FerristrunziteHide

Type:
Biaxial (+)
RI values:
nα = 1.664 nβ = 1.698 nγ = 1.757
2V:
Measured: 77° , Calculated: 78°
Birefringence:
0.093
Max. Birefringence:
δ = 0.093
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:
Very High (positive)
Relative to Canada balsam mounting medium (n ≈ 1.537).

This shows the grain boundary and Becke line effect under plane-polarised light, based on the contrast between this mineral's average refractive index and the mounting medium. It does not take into account mineral colouration.
In focus
Interference Figure:
This shows the idealized biaxial acute bisectrix (Bxa) interference figure - the conoscopic view for a grain cut perpendicular to the acute bisectrix, using this mineral's 2V. The two small white dots mark the melatopes - the points where the two optic axes emerge - and are shown only when they fall within the field of view. The coloured bands are isochromatics, and the dark bands are isogyres.

Rotate the stage: at 0°/90° the isogyres form a cross through the melatopes; at 45° they pull apart into curved hyperbolas. That splitting on rotation - absent in a uniaxial figure - is the standard diagnostic test for telling biaxial minerals from uniaxial ones. If 2V is large, the melatopes may fall outside the field of view, as they often do at the microscope too.
Dispersion:
strong
Optical Extinction:
Z^c ~ 17°
Pleochroism:
Visible
Comments:
X = greenish-yellow, Z = brownish yellow

Chemistry of FerristrunziteHide

Mindat Formula:
Fe3+Fe3+2(PO4)2(OH)3 · 5H2O
Element Weights:
Element% weight
O51.344 %
Fe33.603 %
P12.425 %
H2.628 %

Calculated from ideal end-member formula.
O
Fe
P
H
Elements listed:
Fe, H, O, P - search for minerals with similar chemistry

Chemical AnalysisHide

Crystallography of FerristrunziteHide

Crystal System:
Triclinic
Cell Parameters:
a = 10.012 Å, b = 9.732 Å, c = 7.334 Å
α = 90.50°, β = 96.99°, γ = 116.43°
Ratio:
a:b:c = 1.029 : 1 : 0.754
Unit Cell V:
633.56 ų (Calculated from Unit Cell)
Z:
2
Comment:
Point Group: 1 or 1; Space Group: P1 or P1.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
8.87 Å(80)
5.34 Å(100)
4.48 Å(20)
4.20 Å(30)
3.442 Å(30)
3.387 Å(30)
3.267 Å(40)

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 7: Great Oxidation Event<2.4
47a : [Near-surface hydration of prior minerals]
47c : [Carbonates, phosphates, borates, nitrates]
Geological Setting:
Granite pegmatites, sedimentary phosphate nodules.

Type Occurrence of FerristrunziteHide

Type Locality:
ⓘ Mont-des-Groseillers, Blaton, Bernissart, Hainaut, Wallonia, Belgium
General Appearance of Type Material:
Tan radiating acicular crystals.
Place of Conservation of Type Material:
National Museum of Natural History (Smithsonian Institution), Washington, D.C., USA, catalogue number 162499.
Geological Setting of Type Material:
Fracture filling in a sedimentary rock.
Associated Minerals at Type Locality:
BerauniteCacoxeniteStrengite
Reference:
Peacor, D.R., Dunn, P.J., Simmons, W.B., Ramik, R.A. (1987) Ferristrunzite, a new member of the strunzite group, from Blaton, Belgium. Neues Jahrbuch für Mineralogie, Monatshefte 1987, Heft 10, 453-457.

Synonyms of FerristrunziteHide

Other Language Names for FerristrunziteHide

Relationship of Ferristrunzite to other SpeciesHide

Member of:
Strunzite Group
Other Members of Strunzite Group:
FerrostrunziteFe2+Fe3+2(PO4)2(OH)2 · 6H2OTric.
StrunziteMn2+Fe3+2(PO4)2(OH)2 · 6H2OTric. 1 : P1
ZincostrunziteZnFe3+2(PO4)2(OH)2 · 6.5H2OTric. 1 : P1

Common AssociatesHide

Associations Based on Photo Data:
44 photos of Ferristrunzite associated with CacoxeniteFe3+24AlO6(PO4)17(OH)12 · 75H2O
42 photos of Ferristrunzite associated with BerauniteFe3+6(PO4)4O(OH)4 · 6H2O
39 photos of Ferristrunzite associated with StrengiteFePO4 · 2H2O
16 photos of Ferristrunzite associated with FerroberauniteFe2+Fe3+5(PO4)4(OH)5 · 6H2O
13 photos of Ferristrunzite associated with Rockbridgeite(Fe2+0.5Fe3+0.5)2Fe3+3(PO4)3(OH)5
10 photos of Ferristrunzite associated with WhitmoreiteFe2+Fe3+2(PO4)2(OH)2 · 4H2O
8 photos of Ferristrunzite associated with MitridatiteCa2Fe3+3(PO4)3O2 · 3H2O
6 photos of Ferristrunzite associated with PhosphosideriteFePO4 · 2H2O
2 photos of Ferristrunzite associated with CopiapiteFe2+Fe3+4(SO4)6(OH)2 · 20H2O
1 photo of Ferristrunzite associated with FerrolaueiteFe2+Fe3+2(PO4)2(OH)2 · 8H2O

Related Minerals - Strunz-mindat GroupingHide

8.DC.FerroberauniteFe2+Fe3+5(PO4)4(OH)5 · 6H2OMon. 2/m : B2/b
8.DC.CésarferreiraiteFe2+ Fe3+2(AsO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.FerrivauxiteFe3+Al2(PO4)2(OH)3 · 5H2OTric. 1 : P1
8.DC.IanbruceiteZn2(AsO4)(OH) · 3H2OMon. 2/m : P21/b
8.DC.05NissoniteCu2Mg2(PO4)2(OH)2 · 5H2OMon. 2/m : B2/b
8.DC.07EuchroiteCu2(AsO4)(OH) · 3H2OOrth. 222 : P212121
8.DC.10LegranditeZn2(AsO4)(OH) · H2OMon. 2/m : P21/b
8.DC.12StrashimiriteCu8(AsO4)4(OH)4 · 5H2OMon.
8.DC.15EarlshannoniteMn2+Fe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15KunatiteCuFe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15'UM2006-27-PO:FeHZn'ZnFe3+2(PO4)2(OH)2 · 4H2OMon.
8.DC.15'UKI-2006-(PO:AlCuFeH)'Fe2+Al3+2(PO4)2(OH)2 · 4H2O
8.DC.15CobaltarthuriteCoFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15ArthuriteCuFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15OjuelaiteZnFe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15WhitmoreiteFe2+Fe3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.15BendadaiteFe2+Fe3+2(AsO4)2(OH)2 · 4H2OMon. 2/m : P21/b
8.DC.17KleemaniteZnAl2(PO4)2(OH)2 · 3H2OMon.
8.DC.20MagnesiobermaniteMgMn3+2(PO4)2(OH)2 · 4H2OMon. 2 : P21
8.DC.20BermaniteMn2+Mn3+2(PO4)2(OH)2 · 4H2OMon. 2/m : P2/b
8.DC.20CoralloiteMn2+Mn3+2(AsO4)2(OH)2 · 4H2OTric. 1 : P1
8.DC.22KovdorskiteMg2(PO4)(OH) · 3H2OMon. 2/m : P21/b
8.DC.25ZincostrunziteZnFe3+2(PO4)2(OH)2 · 6.5H2OTric. 1 : P1
8.DC.25MetavauxiteFe2+Al2(PO4)2(OH)2 · 8H2OMon. 2/m : P21/b
8.DC.25MetavivianiteFe2+Fe3+2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.25StrunziteMn2+Fe3+2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.25FerrostrunziteFe2+Fe3+2(PO4)2(OH)2 · 6H2OTric.
8.DC.27BerauniteFe3+6(PO4)4O(OH)4 · 6H2OMon. m : Bb
8.DC.27TvrdýiteFe2+Fe3+2Al3(PO4)4(OH)5(H2O)4 · 2H2OMon. 2/m : B2/b
8.DC.27ZincoberauniteZnFe3+5(PO4)4(OH)5 · 6H2OMon. 2/m : B2/b
8.DC.30MaghrebiteMgAl2(AsO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30FerrolaueiteFe2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30UshkoviteMgFe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30LaueiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30ParavauxiteFe2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30SigloiteFe3+Al2(PO4)2(OH)3 · 7H2OTric. 1 : P1
8.DC.30NordgauiteMnAl2(PO4)2(F,OH)2 · 5H2OTric. 1 : P1
8.DC.30Kayrobertsonite[MnAl2(PO4)2(OH)2(H2O)4] · 2H2OTric. 1 : P1
8.DC.30KummeriteMn2+Fe3+Al(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30MangangordoniteMn2+Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30StewartiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30GordoniteMgAl2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30Kastningite(Mn2+,Fe2+,Mg)Al2(PO4)2(OH)2 · 8H2OTric. 1 : P1
8.DC.30PseudolaueiteMn2+Fe3+2(PO4)2(OH)2 · 8H2OMon. 2/m : P21/b
8.DC.32KamarizaiteFe3+3(AsO4)2(OH)3 · 3H2OTric. 1 : P1
8.DC.32TinticiteFe3+3(PO4)2(OH)3 · 3H2OTric. 1 : P1
8.DC.35VauxiteFe2+Al2(PO4)2(OH)2 · 6H2OTric. 1 : P1
8.DC.37VantasseliteAl4(PO4)3(OH)3 · 9H2OOrth.
8.DC.40CacoxeniteFe3+24AlO6(PO4)17(OH)12 · 75H2OHex. 6/m : P63/m
8.DC.45SouzaliteMg3Al4(PO4)4(OH)6 · 2H2OTric. 1
8.DC.45Gormanite(Fe2+,Mg)3(Al,Fe3+)4(PO4)4(OH)6 · 2H2OTric.
8.DC.47KingiteAl3(PO4)2F2(OH) · 7H2OTric.
8.DC.50AllanpringiteFe3+3(PO4)2(OH)3 · 5H2OMon. 2/m : P21/m
8.DC.50FluorwavelliteAl3(PO4)2(OH)2F · 5H2OOrth. mmm(2/m2/m2/m)
8.DC.50WavelliteAl3(PO4)2(OH)3 · 5H2OOrth. mmm(2/m2/m2/m)
8.DC.52KribergiteAl5(PO4)3(SO4)(OH)4 · 4H2OTric. 1 : P1
8.DC.55MapimiteZn2Fe3+3(AsO4)3(OH)4 · 10H2OMon. m : Bm
8.DC.57OgdensburgiteCa2Fe3+4(Zn,Mn2+)(AsO4)4(OH)6 · 6H2OOrth. mmm(2/m2/m2/m) : Cmmm
8.DC.60CloncurryiteCu0.5(VO)0.5Al2(PO4)2F2 · 5H2OMon. 2/m : P21/b
8.DC.60Nevadaite(Cu2+,Al,V3+)6Al8(PO4)8F8(OH)2 · 22H2OOrth. mmm(2/m2/m2/m)
8.DC.62KenngottiteMn2+3Fe3+4(PO4)4(OH)6(H2O)2 Mon. 2/m : P2/b
8.DC.67MolinelloiteCu(H2O)(OH)V4+O(V5+O4)Tric. 1 : P1
8.DC.70WhitecapsiteH16Fe2+5Fe3+14Sb3+6(AsO4)18O16 · 120H2OHex. 6/m : P63/m
8.DC.75HeimitePbCu2(AsO4)(OH)3 · 2H2OMon. 2/m
8.DC.80LedneviteCu[PO3(OH)] · H2OMon. 2/m : P21/b

Fluorescence of FerristrunziteHide

In UV light:
Not fluorescent in UV

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 FerristrunziteHide

References for FerristrunziteHide

Localities for FerristrunziteHide

Showing 16 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.
Hide all sections | Show all sections

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.
Belgium (TL)
 
  • Wallonia
    • Hainaut
      • Bernissart
        • Blaton
Van Tassel (1966) +8 other references
    • Liège
      • Visé
Jockin (en collaboration avec l'université de Liège)
    • Namur
      • Anhée
Dillen et al. (1990) +2 other references
Brazil
 
  • Minas Gerais
    • Conselheiro Pena
      • Barra do Cuieté
Baijot et al. (2014)
Czech Republic
 
  • Karlovy Vary Region
    • Cheb District
      • Aš
Breiter K.
France
 
  • Occitanie
    • Tarn
      • Castres
        • Fontrieu
          • Fumade
Favreau et al. (2013)
Germany
 
  • Bavaria
    • Upper Palatinate
      • Neustadt an der Waldnaab District
        • Waidhaus
Kastning et al. (1996) +2 other references
  • North Rhine-Westphalia
    • Arnsberg
      • Hochsauerlandkreis
        • Arnsberg
www.handbookofmineralogy.org (n.d.)
      • Märkischer Kreis
        • Iserlohn
          • Letmathe
            • Helmke quarry nature reserve
Bender et al. (1994) +1 other reference
    • Düsseldorf
      • Wuppertal
        • Aprath castle
Emser Hefte 1988 (4)
  • Saxony
    • Görlitz District
      • Neißeaue
Witzke et al. (2013)
  • Thuringia
    • Nordhausen District
      • Harztor
        • Herrmannsacker
          • Lange Tal
            • Neustadt dam
Gröbner et al. (2011)
Poland
 
  • Lower Silesian Voivodeship
    • Wrocław County
      • Gmina Kobierzyce
Ł. Kruszewski PXRD & pXRF data (paper in preparation)
Portugal
 
  • Guarda
    • Gouveia
      • Folgosinho
Alves (2016)
USA
 
  • Wisconsin
    • Rusk County
      • Ladysmith
wgnhs.uwex.edu (n.d.)
Mars
 
  • Aeolis quadrangle
    • Gusev Crater
      • Columbia Hills
        • Husband Hill
          • Cumberland Ridge
Lane et al. (2008)
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