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Ferromerrillite

A valid IMA mineral species
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02239630017271928345905.jpg
George P. Merrill
Formula:
Ca9NaFe2+(PO4)7
Colour:
Colourless
Lustre:
Vitreous
Hardness:
5
Specific Gravity:
3.11 (Calculated)
Crystal System:
Trigonal
Name:
Named for being the Fe2+ (ferro) dominant analogue of merrillite. The root name is for George P. Merrill (1854-1929), Curator of Geology, U.S. National Museum (Smithsonian Institution).
Fe2+-dominant analogue of Merrillite.

Chemically similar to 'ferrohagendorfite' and kapundaite (the latter contains water); somewhat similar to wicksite.

Grains are strongly deformed (7-degree angular mosaicity) due to impact shock, but that was not high enough (not over 23 GPa) for the transformation to tuite.


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Unique IdentifiersHide

Mindat ID:
31308
Long-form identifier:
mindat:1:1:31308:9

IMA Classification of FerromerrilliteHide

Classification of FerromerrilliteHide

Strunz-mindat (2026):
8.AC.45

8 : PHOSPHATES, ARSENATES, VANADATES
A : Phosphates, etc. without additional anions, without H2O
C : With medium-sized and large cations
Dana 8th ed.:
38.3.4.7

38 : ANHYDROUS NORMAL PHOSPHATES, ARSENATES, AND VANADATES
3 : (AB)3(XO4)2

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

Physical Properties of FerromerrilliteHide

Lustre:
Vitreous
Transparency:
Transparent
Colour:
Colourless
Streak:
White
Hardness:
5 on Mohs scale
Cleavage:
None Observed
Density:
3.11 g/cm3 (Calculated)

Optical Data of FerromerrilliteHide

Type:
Uniaxial (-)
RI values:
nω = 1.623 - 1.624 nε = 1.621
Max. Birefringence:
δ = 0.002 - 0.003
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:
may be anomalously biaxial
Pleochroism:
Non-pleochroic

Chemistry of FerromerrilliteHide

Mindat Formula:
Ca9NaFe2+(PO4)7
Element Weights:
Element% weight
O40.566 %
Ca32.662 %
P19.633 %
Fe5.057 %
Na2.082 %

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

Crystallography of FerromerrilliteHide

Crystal System:
Trigonal
Class (H-M):
3m - Ditrigonal Pyramidal
Space Group:
R3c
Cell Parameters:
a = 10.372 Å, c = 37.217 Å
Ratio:
a:c = 1 : 3.588
Unit Cell V:
3,467.34 ų (Calculated from Unit Cell)
Morphology:
grains
Comment:
data for the Shergotty occurrence

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
2.860 Å(100)
3.19 Å(60)
2.594 Å(50)
8.13 Å(20)
6.42 Å(20)
2.747 Å(20)
1.917 Å(20)
1.885 Å(20)
1.868 Å(20)
1.715 Å(20)
Comments:
Shergotty meteorite. Data from the type description.

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
Stage 2: Planetesimal differentiation and alteration4.566-4.550
6 : Secondary asteroid phases4.566-4.560

Type Occurrence of FerromerrilliteHide

Type Locality:
ⓘ Shergotty Martian meteorite, Gaya District, Bihar, India
General Appearance of Type Material:
Anhedral grains to 20–50 µm.
Place of Conservation of Type Material:
A.E. Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia (3514/1).
Geological Setting of Type Material:
Martian meteorites (basaltic and olivine-phyric shergottites).
Reference:
Britvin, Sergey N.; Krivovichev, Sergey V.; Armbruster, Thomas (2016) Ferromerrillite, Ca9NaFe2+(PO4)7, a new mineral from the Martian meteorites, and some insights into merrillite–tuite transformation in shergottites. European Journal of Mineralogy, 28 (1). 125-136 doi:10.1127/ejm/2015/0027-2508

Synonyms of FerromerrilliteHide

Other Language Names for FerromerrilliteHide

Relationship of Ferromerrillite to other SpeciesHide

Member of:
Merrillite Subgroup > Merrillite Group > Cerite Supergroup
Other Members of Merrillite Subgroup:
KepleriteCa9(Ca0.5◻0.5)Mg(PO4)7Trig. 3m : R3c
MatyhiteCa18(Ca,◻)2Fe2+2(PO4)14Trig. 3m : R3c
MerrilliteCa9NaMg(PO4)7Trig. 3m : R3m

Related Minerals - Strunz-mindat GroupingHide

8.AC.'Crocobelonite-1M'CaFe3+2O(PO4)2Mon. 2/m : P21/m
8.AC.MagnesioqingheiiteNa2Mg(MgAl)(PO4)3Mon. 2/m
8.AC.ManganobadaloviteNaNaMn(MgFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.Changesite-(Y)(Ca8Y)◻Fe2+(PO4)7Trig. 3m : R3c
8.AC.Babunaite-(Nd)NdAsO4Tet. 4/m : I41/a
8.AC.CrocobeloniteCaFe3+2O(PO4)2Orth. mmm(2/m2/m2/m) : Pnma
8.AC.WopmayiteCa6Na3◻Mn(PO4)3(PO3OH)4 Trig. 3m : R3c
8.AC.BeershevaiteCaFe3+3(PO4)3OMon. 2/m : P21/m
8.AC.Epiebnerite(NH4)Zn(PO4)Mon. 2 : P21
8.AC.Ebnerite(NH4)Zn(PO4)Hex. 6 : P63
8.AC.XDyrnaesite-(La)Na8Ce4+(La,REE)2(PO4)6Orth. mmm(2/m2/m2/m) : Pnma
8.AC.EdtolliteK2NaCu5Fe3+O2(AsO4)4Tric. 1 : P1
8.AC.AngarfiteNaFe3+5(PO4)4(OH)4 · 4H2O Orth. 222 : C2221
8.AC.KabaloviteFe2+3Fe3+4(PO4)6Tric. 1 : P1
8.AC.Nazarchukite Ca2NiFe3+2(PO4)4Orth. mmm(2/m2/m2/m) : Pbca
8.AC.CalciohatertiteNaNaCa(CaFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.AlumoedtolliteK2NaCu5AlO2(AsO4)4Tric. 1 : P1
8.AC.02GrigorieviteCu3Fe3+2Al2(VO4)6Tric. 1 : P1
8.AC.02KoksharoviteCaMg2Fe3+4(VO4)6Tric. 1 : P1
8.AC.02ZiminaiteFe3+ 6 (VO4)6Tric. 1 : P1
8.AC.05HatertiteNa2(Ca,Na)(Fe3+,Cu)2(AsO4)3Mon. 2/m : B2/b
8.AC.05ErikapohliteCu3(Zn,Cu,Mg)4Ca2(AsO4)6 · 2H2OMon. 2/m : B2/m
8.AC.05'Unnamed (Na-Mg Arsenate Hydroxyarsenate)'NaMg3(AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05'Unnamed (Na-Zn-H Arsenate Hydroxyarsenate)'Na(Na0.6Zn0.4)Zn2(H0.6AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05CalciojohilleriteNaCaMg3(AsO4)3Mon. 2/m : B2/b
8.AC.05Magnesiohatertite(Na,Ca)2Ca(Mg,Fe3+)2(AsO4)3Mon. 2/m : B2/b
8.AC.05 va'Alluaudite-Na[]'◻4Na4Mn2+4Fe3+8(PO4)12Mon. 2/m : B2/b
8.AC.05 va'Alluaudite-Ca[]'◻4Ca4Mn2+4Fe3+8(PO4)12Mon. 2/m : B2/b
8.AC.05 va'Ferroalluaudite-NaNa'Na4Na4Fe2+4Fe3+8(PO4)12Mon. 2/m : B2/m
8.AC.05'Hagendorfite-NaNa'NaNaFe2+(Mn2+,Mn3+)(PO4)3 (?)Mon. 2/m : B2/b
8.AC.05O'DanieliteNa(Zn,Mg)3(AsO4)(AsO3OH)2Mon. 2/m : B2/b
8.AC.05HowardevansiteNaCuFe2(VO4)3Tric. 1 : P1
8.AC.05KhrenoviteNa3Fe3+2(AsO4)3Mon. 2/m : B2/b
8.AC.05ZincobradaczekiteNaZn2Cu2(AsO4)3Mon. 2/m : B2/b
8.AC.05ParaberzeliiteNaCa2Mg2(AsO4)3Mon. 2/m : B2/b
8.AC.05BadaloviteNa2Mg2Fe(AsO4)3Mon. 2/m : B2/b
8.AC.05MagnesiocanutiteNaMnMg2[AsO4]2[AsO2(OH)2]Mon. 2/m : B2/b
8.AC.05ManganohatertiteNaNaCa(MnFe3+)(AsO4)3Mon. 2/m : B2/b
8.AC.05CamanchacaiteNaCaMg2[AsO4][AsO3(OH)]2Mon. 2/m : B2/b
8.AC.07ZhanghuifeniteNa3Mn4Mg2Al(PO4)6Mon. 2/m
8.AC.07FerrobobfergusoniteNa2Fe2+5Fe3+Al(PO4)6Mon.
8.AC.10HagendorfiteNaCaMn2+Fe2+2(PO4)3Mon. 2/m : B2/b
8.AC.10'Ferrohagendorfite'NaCaFe2+Fe2+2(PO4)3Mon.
8.AC.10JohilleriteNa(Mg,Zn)3Cu(AsO4)3Mon. 2/m : B2/b
8.AC.10VaruliteNaCaMn2+Mn2+2(PO4)3Mon. 2/m : B2/b
8.AC.10NickenichiteNa0.8Ca0.4Cu0.4(Mg,Fe)3(AsO4)3Mon. 2/m : B2/b
8.AC.10ArseniopleiteNaCaMnMn2(AsO4)3Mon. 2/m
8.AC.10GroatiteNaCaMn2(PO4)[PO3(OH)]2Mon. 2/m : B2/b
8.AC.10Alluaudite(Na,Ca)Mn2+(Fe3+,Mn2+,Fe2+,Mg)2(PO4)3Mon. 2/m : B2/b
8.AC.10BradaczekiteNaCu4(AsO4)3Mon. 2/m : B2/b
8.AC.10Caryinite(Na,Pb)(Ca,Na)CaMn2+2(AsO4)3Mon. 2/m
8.AC.10Ferroalluaudite(Na,Ca)Fe2+(Fe3+,Mn2+,Fe2+)2(PO4)3Mon. 2/m : B2/b
8.AC.10Maghagendorfite(Na,◻)MgMn2+(Fe2+,Fe3+)2(PO4)3Mon. 2/m
8.AC.15Ferrowyllieite(Na,Ca,Mn)(Fe,Mn)(Fe,Fe,Mg)Al(PO4)3Mon. 2/m : P21/b
8.AC.15QingheiiteNaNaMn2+(MgAl)(PO4)3Mon. 2/m : P21/b
8.AC.15Rosemaryite(Na,Ca,Mn)(Mn,Fe2+)(Fe3+,Mg)Al(PO4)3Mon. 2/m : P21/b
8.AC.15FerroqingheiiteNaNaFe2+(MgAl)(PO4)3Mon. 2/m : P21/m
8.AC.15Ferrorosemaryite◻NaFe2+Fe3+Al(PO4)3Mon. 2/m
8.AC.15BobfergusoniteNa2Mn5FeAl(PO4)6Mon. 2/m : P2/b
8.AC.15Wyllieite(Na,Ca,Mn)(Mn,Fe)(Fe,Mg)Al(PO4)3Mon. 2/m
8.AC.17CzochralskiiteNa4Ca3Mg(PO4)4Orth. mmm(2/m2/m2/m) : Pnma
8.AC.18ManitobaiteNa16Mn2+ 25Al8(PO4)30Mon. m : Pb
8.AC.20MarićiteNaFe2+(PO4)Orth. mmm(2/m2/m2/m) : Pmna
8.AC.25Schäferite(NaCa2)Mg2(VO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25Berzeliite(NaCa2)Mg2(AsO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25MatyhiteCa18(Ca,◻)2Fe2+2(PO4)14Trig. 3m : R3c
8.AC.25Hedegaardite(Ca,Na)9(Ca,Na)Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.25Manganberzeliite(NaCa2)Mn2+2(AsO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.25Palenzonaite(NaCa2)Mn2+2(VO4)3Iso. m3m(4/m32/m) : Ia3d
8.AC.30BrianiteNa2CaMg(PO4)2Mon. 2/m : P21/b
8.AC.35Vitusite-(Ce)Na3(Ce,La,Nd)(PO4)2Orth. mm2 : Pca21
8.AC.40Bario-olgite(Ba,Sr)(Na,Sr,REE)2Na(PO4)2 · Trig. 3 : P3
8.AC.40Olgite(Sr,Ba)(Na,Sr,REE)2Na(PO4)2Trig. 3m(32/m) : P3m1
8.AC.45Magnesiochangesite-(Ce)(Ca8Ce)◻Mg(PO4)7Trig. 3m : R3c
8.AC.45TuiteCa3(PO4)2Trig. 3m(32/m) : R3m
8.AC.45StrontiowhitlockiteSr9Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.45Magnesiochangesite-(Y)(Ca8Y)◻ Mg(PO4)7Trig. 3m : R3m
8.AC.45Changesite-(Ce)(Ca8Ce)◻Fe2+(PO4)7Trig. 3m : R3c
8.AC.45MerrilliteCa9NaMg(PO4)7Trig. 3m : R3m
8.AC.45WhitlockiteCa9Mg(PO4)6(PO3OH)Trig. 3m : R3c
8.AC.47IwateiteNa2BaMn(PO4)2Trig. 3 : P3
8.AC.47OzerovaiteNa2KAl3(AsO4)4Orth. mmm(2/m2/m2/m) : Cmca
8.AC.47YurmariniteNa7(Fe3+,Mg,Cu)4(AsO4)6Trig. 3m(32/m) : R3c
8.AC.47PansneriteK3Na3(Fe3+,Al)6(AsO4)8Orth. mmm(2/m2/m2/m)
8.AC.47AnatolyiteNa6(Ca,Na)(Mg,Fe3+)3Al(AsO4)6Trig. 3m(32/m) : R3c
8.AC.50FillowiteNa3CaMn2+11(PO4)9Trig. 3 : R3
8.AC.50GalileiiteNa3Fe2+Fe2+11(PO4)9Trig. 3 : R3
8.AC.50JohnsomervilleiteNa3CaFe11(PO4)9Trig. 3 : R3
8.AC.50XenophylliteNa4Fe2+7(PO4)6Tric. 1 : P1
8.AC.50UdinaiteNaMg4(VO4)3Tet. 42m : I42d
8.AC.50ArsenudinaiteNaMg4(AsO4)3Tet. 42m : I42d
8.AC.50ChladniiteNa3CaMg11(PO4)9Trig. 3 : R3
8.AC.52Lasnierite(Ca,Sr)(Mg,Fe2+)2Al(P[O,F]4)3Orth. mmm(2/m2/m2/m) : Pbcn
8.AC.55PharmazinciteKZnAsO4Hex. 6 : P63
8.AC.57ZubkovaiteCa3Cu3(AsO4)4Mon. 2 : B2
8.AC.60KosnariteKZr2(PO4)3Trig. 3m(32/m) : R3c
8.AC.65Panethite(Na,Ca)2(Mg,Fe2+)2(PO4)2Mon. 2/m : P21/b
8.AC.70StanfielditeCa4Mg5(PO4)6Mon.
8.AC.75RonneburgiteK2MnV4O12Mon. 2/m
8.AC.80TillmannsiteAg3Hg[(V,As)O4]Tet. 4 : I4
8.AC.85FilatoviteK(Al,Zn)2(As,Si)2O8Mon. 2/m

Fluorescence of FerromerrilliteHide

In UV light:
Not fluorescent under LW or SW.

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 FerromerrilliteHide

References for FerromerrilliteHide

Localities for FerromerrilliteHide

Showing 6 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.
India (TL)
 
  • Bihar
    • Gaya District
Britvin et al. (2016)
Israel
 
  • Southern District
    • Beersheba Subdistrict
      • Tamar Regional Council
        • Hatrurim Basin
          • Wadi Zohar
Galuskin et al. (2025)
Palau
 
  • Angaur
    • Angaur Island
      • Ngeramasch
Färber (n.d.)
Poland
 
  • Lower Silesian Voivodeship
    • Świdnica County
      • Gmina Świdnica
Pieczka et al. (2015)
Pieczka et al. (2015)
Pieczka et al. (2017)
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