Brannockite Mineral Data
General Brannockite Information
Chemical Formula:
KSn2Li3Si12O30
Composition:
Molecular Weight = 1,114.35 gm
Potassium 3.51 % K 4.23 % K2 O
Lithium 1.87 % Li 4.02 % Li2 O
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:
KSn2 Li3 Si12 O30
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 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
X Ray Diffraction:
By Intensity(I/Io ): 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:
PEBrannockite = 62.57 barns/electronU=PEBrannockite 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:
Notes:
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