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Mcgillite

A valid IMA mineral species
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05197920017271925001104.jpg
Mcgillite

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
04139500017271925036970.jpg
Mcgillite, etc.

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
04233940017271925062578.jpg
Mcgillite

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
05197920017271925001104.jpg
Mcgillite

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
04139500017271925036970.jpg
Mcgillite, etc.

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
04233940017271925062578.jpg
Mcgillite

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
05197920017271925001104.jpg
Mcgillite

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
04139500017271925036970.jpg
Mcgillite, etc.

Sullivan Mine, Kimberley, Fort Steele Mining Division, British Columbia, Canada
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About McgilliteHide

01241390017271925115055.png
McGill University Coat of Arms
Formula:
(Mn,Fe)8Si6O15(OH)8Cl2
Hardness:
5
Crystal System:
Monoclinic
Name:
Named by Gabrielle Donnay, M. Bétournay, and G. Hamil in recognition of McGill University, Montreal, Quebec, Canada and its contributions to mineralogy.
Isostructural with:
Pyrosmalite Group
May be regarded as an ordered equivalent of friedelite (Ozawa et al., 1983).

Chemically very similar to pyrosmalite-(Mn).


Unique IdentifiersHide

Mindat ID:
2613
Long-form identifier:
mindat:1:1:2613:6

IMA Classification of McgilliteHide

IMA status:
Approved
IMA Formula:
Mn2+8Si6O15(OH)8Cl2
Approval year:
1979

Classification of McgilliteHide

Strunz-mindat (2026):
9.EE.10

9 : SILICATES (Germanates)
E : Phyllosilicates
E : Single tetrahedral nets of 6-membered rings connected by octahedral nets or octahedral bands
Dana 8th ed.:
72.4.1b.2

72 : PHYLLOSILICATES Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
4 : Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings with 4-, 6-, and 12-membered rings
Hey's CIM Ref.:
17.3.16

17 : Silicates Containing other Anions
3 : Silicates with chloride (including aluminosilicates)

Mineral SymbolsHide

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

Please only use the official IMA–CNMNC symbol. Older variants are listed for historical use only.

SymbolSourceReference for Standard
McgIMA–CNMNCWarr, L.N. (2021). IMA–CNMNC approved mineral symbols. Mineralogical Magazine, 85(3), 291-320. doi:10.1180/mgm.2021.43
McgWarr (2020)Warr, L.N. (2020) Recommended abbreviations for the names of clay minerals and associated phases. Clay Minerals, 55, 261–264 doi:10.1180/clm.2020.30

Physical Properties of McgilliteHide

Hardness:
5 on Mohs scale

Optical Data of McgilliteHide

Type:
Biaxial (-)
RI values:
nω = 1.6685 n = 1.6415
Birefringence:
0.027
Surface Relief:
Moderate
Dispersion:
relatively weak
Pleochroism:
Non-pleochroic

Chemistry of McgilliteHide

Mindat Formula:
(Mn,Fe)8Si6O15(OH)8Cl2
Element Weights:
Element% weight
Mn41.660 %
O34.881 %
Si15.973 %
Cl6.721 %
H0.764 %

Calculated from ideal end-member formula.
Elements listed:
Cl, Fe, H, Mn, O, Si - search for minerals with similar chemistry
Common Impurities:
As,Zn,Mg,Ca,H2O

Crystallography of McgilliteHide

Crystal System:
Monoclinic
Class (H-M):
2/m - Prismatic
Space Group:
B2/m
Setting:
C12/m1
Cell Parameters:
a = 23.31 Å, b = 13.45 Å, c = 7.42 Å
β = 105.17°
Ratio:
a:b:c = 1.733 : 1 : 0.552
Unit Cell V:
2,245.25 ų (Calculated from Unit Cell)
Twinning:
Universal, repeated about monoclinic [110] and [1-10], composition plane {001}, giving pseudorhombohedral symmetry.

X-Ray Powder DiffractionHide

Powder Diffraction Data:
d-spacingIntensity
11.67 Å(20)
7.16 Å(70)
6.75 Å(10)
6.50 Å(10)
5.44 Å(10)
3.570 Å(40)
2.888 Å(60)
2.560 Å(100)
2.409 Å(20)
2.112 Å(40)
1.971 Å(20)
1.727 Å(20)
1.683 Å(40)
1.638 Å(20)
1.619 Å(20)
1.524 Å(10)
1.454 Å(10)
1.420 Å(20)
1.356 Å(20)
1.317 Å(10)
1.292 Å(10)
1.205 Å(10)
1.167 Å(10)
1.100 Å(10)
1.0897 Å(10)
1.0795 Å(20)
Comments:
Nearly identical to that of friedelite. Data from: Donnay, G., M. Bétournay, and G. Hamill (1980): McGillite, a new manganous hydroxychlorosilicate. Canadian Mineralogist 18, 31-36. [Abstract: American Mineralogist (1981): 66: 1276.]

Geological EnvironmentHide

Paragenetic Mode(s):
Paragenetic ModeEarliest Age (Ga)
High-? alteration and/or metamorphism
32 : Ba/Mn/Pb/Zn deposits, including metamorphic deposits

Type Occurrence of McgilliteHide

Synonyms of McgilliteHide

Other Language Names for McgilliteHide

Relationship of Mcgillite to other SpeciesHide

Member of:
Pyrosmalite Group
Other Members of Pyrosmalite Group:
FriedeliteMn2+8Si6O15(OH,Cl)10Mon. 2/m : B2/m
NeleniteMn2+16As3+3Si12O36(OH)17Trig. 3m(32/m) : R3m
Pyrosmalite-(Fe)Fe2+8Si6O15(OH,Cl)10Trig. 3m(32/m) : P3m1
Pyrosmalite-(Mn)Mn2+8Si6O15(OH,Cl)10Trig. 3m(32/m) : P3m1
SchalleriteMn2+16As3Si12O36(OH)17Trig. 3m : P3m1

Common AssociatesHide

Associations Based on Photo Data:
5 photos of Mcgillite associated with SphaleriteZnS
3 photos of Mcgillite associated with BoulangeritePb5Sb4S11
3 photos of Mcgillite associated with CalciteCaCO3
3 photos of Mcgillite associated with PyriteFeS2
3 photos of Mcgillite associated with QuartzSiO2

Related Minerals - Strunz-mindat GroupingHide

9.EE.CairncrossiteSr2Ca7-xNa2x(Si4O10)4(OH)2(H2O)15-xTric. 1 : P1
9.EE.05BementiteMn7Si6O15(OH)8Mon.
9.EE.07InnsbruckiteMn33(Si2O5)14(OH)38Mon. m : Bm
9.EE.10'Brokenhillite'Mn8Si6O15(OH)10Hex. 6mm : P63mc
9.EE.10FriedeliteMn2+8Si6O15(OH,Cl)10Mon. 2/m : B2/m
9.EE.10Pyrosmalite-(Mn)Mn2+8Si6O15(OH,Cl)10Trig. 3m(32/m) : P3m1
9.EE.10Pyrosmalite-(Fe)Fe2+8Si6O15(OH,Cl)10Trig. 3m(32/m) : P3m1
9.EE.15NeleniteMn2+16As3+3Si12O36(OH)17Trig. 3m(32/m) : R3m
9.EE.15SchalleriteMn2+16As3Si12O36(OH)17Trig. 3m : P3m1
9.EE.20Palygorskite◻Al2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2OMon. 2/m : B2/m
9.EE.20YofortieriteMn2+Mn2+2Mn2+2◻2Si8O20(OH)2(H2O)4 · 4H2OMon. 2/m : B2/m
9.EE.20WindhoekiteFe3+(Fe3+1.67◻0.33)Ca2◻2Si8O20(OH)2(H2O)4(OH)2 · 6H2OMon. 2/m : B2/m
9.EE.20Windmountainite◻Fe3+2Mg2◻2Si8O20(OH)2(H2O)4 · 4H2OMon. 2/m : B2/m
9.EE.20IkorskyiteKMn3+(Si4O10) · 3H2OMon. 2/m : P21/b
9.EE.20TuperssuatsiaiteFe3+Fe3+2(Na◻)◻2Si8O20(OH)2(H2O)4 · 2H2OMon. 2/m : B2/m
9.EE.20'Unnamed (Na-Ca-Fe-Silicate-Hydrate)'NaCa(Fe2+,Al,Mn)5[Si8O19(OH)](OH)7 · 5H2OTric. 1 : P1
9.EE.25SepioliteMg4(Si6O15)(OH)2 · 6H2OOrth. mmm(2/m2/m2/m) : Pnna
9.EE.25LoughliniteNa2Mg3Si6O16 · 8H2OOrth. mmm(2/m2/m2/m)
9.EE.25Falcondoite(Ni,Mg)4Si6O15(OH)2 · 6H2OOrth.
9.EE.25Kalifersite(K,Na)5Fe3+7Si20O50(OH)6 · 12H2OTric. 1 : P1
9.EE.30OrlymaniteCa4Mn3Si8O20(OH)6 · 2H2OHex.
9.EE.30TungusiteCa4Fe2Si6O15(OH)6Tric. 1 : P1
9.EE.30GyroliteNaCa16Si23AlO60(OH)8 · 14H2OTric. 1 : P1
9.EE.35Reyerite(Na,K)2Ca14(Si,Al)24O58(OH)8 · 6H2OTrig. 3 : P3
9.EE.35KodamaiteNa3(Ca5Na)Si16O36(OH)4F2 · (14-x)H2OTric. 1 : P1
9.EE.35Truscottite(Ca,Mn)14Si24O58(OH)8 · 2H2OTrig.
9.EE.40NatrosiliteNa2Si2O5Mon. 2/m : P21/b
9.EE.45MakatiteNa2Si4O8(OH)2 · 4H2OMon. 2/m : P21/b
9.EE.50VarennesiteNa8Mn2Si10O25(OH,Cl)2 · 12H2OOrth. mmm(2/m2/m2/m) : Cmcm
9.EE.55RaiteMn2+Mn2+2Na2(◻1.75Ti0.25)Si8O20(OH)2(H2O)4 · Na(H2O)6Orth. 222 : C222
9.EE.60IntersiliteNa6Mn2+Ti[Si10O24(OH)](OH)3 · 4H2OMon.
9.EE.65ZakharoviteNa4Mn5Si10O24(OH)6 · 6H2OTrig. 3m
9.EE.65ShafranovskiteNa3K2(Mn,Fe,Na)4[Si9(O,OH)27](OH)2 · nH2OTrig. 3m : P31c
9.EE.70ZeophylliteCa13Si10O28(OH)2F8 · 6H2OTrig. 3 : R3
9.EE.75Minehillite(K,Na)2-3Ca28Zn4Al4Si40O112(OH)16Hex.
9.EE.80Fedorite(Na,K)2-3(Ca4Na3)Si16O38(OH,F)2 · 3.5H2OTric. 1 : P1
9.EE.80Martinite(Na,◻,Ca)12Ca4(Si,S,B)14B2O38(OH,Cl)2F2 · 4H2OTric. 1 : P1
9.EE.80EllingseniteNa5Ca6Si18O38(OH)13 · 6H2OTric. 1 : P1
9.EE.85Lalondeite(Na,Ca)6(Ca,Na)3Si16O38(F,OH)2 · 3H2OTric. 1 : P1

Fluorescence of McgilliteHide

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 McgilliteHide

References for McgilliteHide

Localities for McgilliteHide

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.
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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.
Canada (TL)
 
  • British Columbia
    • Fort Steele Mining Division
      • Kimberley
DONNAY et al. (1980) +3 other references
Japan
 
  • Tochigi Prefecture
    • Nikko City
      • Ashio
DONNAY et al. (1980)
Portugal
 
  • Beja
    • Beja
      • Albernoa e Trindade
        • Albernoa Mining Field
Azevedo (2024)
Romania
 
Hirtopanu (2006)
  • Suceava County
    • Iacobeni
minerals-of-the-carpathians.eu (2008)
Slovakia
 
  • Košice Region
    • Spišská Nová Ves District
      • Poráč
Martin Števko & Pavol Myšľan +1 other reference
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