Brannockite Mineral Data

General Brannockite Information

Chemical Formula:

KSn2Li3Si12O30

Composition:

Molecular Weight = 1,114.35 gm

Potassium 3.51 % K 4.23 % K₂O

Lithium 1.87 % Li 4.02 % Li₂O

Silicon 30.24 % Si 64.70 % SiO₂

Tin 21.31 % Sn 27.05 % SnO₂

Oxygen 43.07 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

KSn₂Li₃Si₁₂O₃₀

IMA Status:

Approved IMA 1973

Locality:

Foote Mineral Co. mine in Kings Mountain, Cleveland County., North Carolina, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Dr. Kent C. Brannock, Chemist, Kingsport, TN.

Name Pronunciation:

Brannockite + Pronunciation

Synonym:

ICSD 202622

PDF 26-853

Brannockite Image

Images:

Brannockite

Comments: Clear, hexagonal plates of brannockite crystals.
Location: Foote mine, Kings Mountain, Cleveland County, North Carolina, USA. Scale: Size Not Given.
© Lou Perloff / Photo Atlas of Minerals

Brannockite Crystallography

Axial Ratios:

a:c = 1:1.42601

Cell Dimensions:

a = 10.002, c = 14.263, Z = 2; V = 1,235.71 Den(Calc)= 2.99

Crystal System:

Hexagonal - Dihexagonal Dipyramidal H-M Symbol (6/m 2/m 2/m) Space Group: P 6/mcc

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 4.109(1), 2.905(0.9), 7.141(0.8),

Physical Properties of Brannockite

Cleavage:

None

Color:

Colorless.

Density:

2.98

Diaphaneity:

Transparent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Hardness:

5-6 - Between Apatite and Orthoclase

Luminescence:

Fluorescent, Short UV=bright blue-white.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Brannockite

Dichroism (e):

colorless.

Dichroism (w):

colorless.

Gladstone-Dale:

CI meas= 0.02 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.023 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1895,KPDmeas= 0.1901,KC= 0.1939
Ncalc = 1.58

Optical Data:

Uniaxial (-), e=1.566, w=1.567, bire=0.0010.

Calculated Properties of Brannockite

Electron Density:

Bulk Density (Electron Density)=2.87 gm/cc
note: Specific Gravity of Brannockite =2.98 gm/cc.

Fermion Index:

Fermion Index = 0.05
Boson Index = 0.95

Photoelectric:

PE_Brannockite= 62.57 barns/electron
U=PE_Brannockite x r_electron= 179.36 barns/cc.

Radioactivity:

GRapi = 48.70 (Gamma Ray American Petroleum Institute Units)
Concentration of Brannockite per GRapi unit = 2.05 (%)

Estimated Radioactivity from Brannockite - barely detectable

Brannockite Classification

Dana Class:

63.02.01a.01 (63)Cyclosilicate Condensed Rings

(63.02)6-membered rings

(63.02.01a)Milarite - Osumilite group (Milarite - Osumilite subgroup)

63.02.01a.01 Brannockite KSn2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.02 Chayesite K(Mg,Fe)4Fe(Si12O30) P 6/mcc 6/m 2/m 2/m

63.02.01a.03 Darapiosite KNa2Zr[Li(Mn,Zr)2Si12O30] P 6/mcc 6/m 2/m 2/m

63.02.01a.04 Eifelite KNa3Mg4Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.05 Merrihueite (K,Na)2(Fe,Mg)5Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.06 Osumilite-(Fe) (K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.07 Osumilite-(Mg) (K,Na)(Mg,Fe)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.08 Poudretteite KNa2B3Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.09 Sugilite KNa2(Fe,Mn,Al)2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.10 Yagiite (Na,K)3Mg4(Al,Mg)6(Si,Al)24O60 P 6/mmc 6/m 2/m 2/m

63.02.01a.11 Dusmatovite K(K,Na,[])(Mn,Y,Zr)2(Zn,Li)3Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.12 Milarite K2Ca4Al2Be4Si24O60•(H2O) P 6/mcc 6/m 2/m 2/m

63.02.01a.13 Sogdianite (K,Na)2(Li,Fe,Al)3ZrSi12O30 P 6/mmm 6/m 2/m 2/m

63.02.01a.14 Roedderite (Na,K)2(Mg,Fe)5Si12O30 P 6₃/mmc 6/m 2/m 2/m

63.02.01a.15 Berezanskite! KLi3Ti2Si12O30 P 6/mcc 6/m 2/m 2/m

63.02.01a.16 Shibkovite! K(Ca,Mn,Na)2(K2-x,[]x)2ZnSi12O30(x~0.8) P 6/mcc 6/m 2/m 2/m

63.02.01a.17 Trattnerite! (Fe,Mg)2(Mg,Fe)3(Si12O30) P 6/mcc 6/m 2/m 2/m

63.02.01a.18 Almarudite! K([],Na)2(Mn,Fe,Mg)2(Be,Al)3[Si12O30] P 6/mcc 6/m 2/m 2/m

63.02.01a.19 Oftedalite! (Sc,Ca)2KBe3Si12O30 P 6/mmc 6/m 2/m 2/m

63.02.01a.20 Klochite ([]1Na1)KFe2Zn3[Si12O30] P 6/mcc 6/m 2/m 2/m

63.02.01a.21 Friedrichbeckeite! K([],Na)Mg2(Be2Mg)Si12O30 P 6/mcc 6/m 2/m 2/m

Strunz Class:

09.CM.05 09 - SILICATES (Germanates)

09.C - Cyclosilicates

09.CM -[Si6O18]12- 6-membered double rings (sechser-Doppelringe)

09.CM.05 Brannockite KSn2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Armenite BaCa2Al6Si9O30•2(H2O) Pnc2 mm2

09.CM.05 Berezanskite! KLi3Ti2Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Dusmatovite K(K,Na,[])(Mn,Y,Zr)2(Zn,Li)3Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Chayesite K(Mg,Fe)4Fe(Si12O30) P 6/mcc 6/m 2/m 2/m

09.CM.05 Shibkovite! K(Ca,Mn,Na)2(K2-x,[]x)2ZnSi12O30(x~0.8) P 6/mcc 6/m 2/m 2/m

09.CM.05 Eifelite KNa3Mg4Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Darapiosite KNa2Zr[Li(Mn,Zr)2Si12O30] P 6/mcc 6/m 2/m 2/m

09.CM.05 Merrihueite (K,Na)2(Fe,Mg)5Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Roedderite (Na,K)2(Mg,Fe)5Si12O30 P 6₃/mmc 6/m 2/m 2/m

09.CM.05 Milarite K2Ca4Al2Be4Si24O60•(H2O) P 6/mcc 6/m 2/m 2/m

09.CM.05 Osumilite-(Fe) (K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Osumilite-(Mg) (K,Na)(Mg,Fe)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Poudretteite KNa2B3Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Sugilite KNa2(Fe,Mn,Al)2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

09.CM.05 Sogdianite (K,Na)2(Li,Fe,Al)3ZrSi12O30 P 6/mmm 6/m 2/m 2/m

09.CM.05 Oftedalite! (Sc,Ca)2KBe3Si12O30 P 6/mmc 6/m 2/m 2/m

09.CM.05 Yagiite (Na,K)3Mg4(Al,Mg)6(Si,Al)24O60 P 6/mmc 6/m 2/m 2/m

09.CM.05 Trattnerite! (Fe,Mg)2(Mg,Fe)3(Si12O30) P 6/mcc 6/m 2/m 2/m

09.CM.05 Almarudite! K([],Na)2(Mn,Fe,Mg)2(Be,Al)3[Si12O30] P 6/mcc 6/m 2/m 2/m

Other Brannockite Information

References:

PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Brannockite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - WWW-MINCRYST

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Print or Cut-and-Paste your Brannockite Specimen Label here :

Brannockite

KSn2Li3Si12O30
Dana No: 63.02.01a.01 Strunz No: 09.CM.05
Locality:

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