Gamagarite Mineral Data
General Gamagarite Information
Chemical Formula:
Ba2(Fe+++,Mn+++)(VO4)2(OH)
Composition:
Molecular Weight = 577.16 gm
Barium 47.59 % Ba 53.13 % BaO
Manganese 2.38 % Mn 3.42 % Mn2 O3
Vanadium 17.65 % V 31.51 % V2 O5
Iron 7.26 % Fe 10.38 % Fe2 O3
Hydrogen 0.17 % H 1.56 % H2 O
Oxygen 24.95 % O
______ ______
100.00 % 100.00 % = TOTAL OXIDE
Empirical Formula:
Ba2 Fe3+ 0.75 Mn3+ 0.25 (VO4 )2 (OH)
Environment:
Banded manganese ore replacing shale.
IMA Status:
Valid Species (Pre-IMA) 1943
Locality:
Along Gamagara Ridge, on Gloucester Farm, about 27 km north of Postmasburg, Cape Province, South Africa. Link to MinDat.org Location Data.
Name Origin:
Named for the locality.
Name Pronunciation:
Gamagarite + Pronunciation
Synonym:
ICSD 68348
PDF 41-1413
Gamagarite Image
Images:
Gamagarite Crystallography
Axial Ratios:
a:b:c =1.4829:1:1.2771
Cell Dimensions:
a = 9.15, b = 6.17, c = 7.88, Z = 2; beta = 112.7° V = 410.41 Den(Calc)= 4.67
Crystal System:
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21 /m
Physical Properties of Gamagarite
Cleavage:
{001} Distinct, {100} Distinct, {101} Indistinct
Color:
Brownish black, Dark brown, Black.
Density:
4.62
Diaphaneity:
Translucent to Opaque
Fracture:
Brittle - Generally displayed by glasses and most non-metallic minerals.
Hardness:
4.5-5 - Near Apatite
Luster:
Adamantine
Optical Properties of Gamagarite
Gladstone-Dale:
CI meas = -0.029 (Excellent) - where the CI = (1-KPDmeas /KC ) CI calc = -0.018 (Superior) - where the CI = (1-KPDcalc /KC )
KPDcalc = 0.2274,KPDmeas = 0.2299,KC = 0.2234 Ncalc = 2.03 - 2.04
Optical Data:
Biaxial (+), a=2.016, b=2.04, g=2.13, bire=0.1140, 2V(Calc)=58, 2V(Meas)=46-62.
Calculated Properties of Gamagarite
Electron Density:
Bulk Density (Electron Density)=4.15 gm/cc note: Specific Gravity of Gamagarite =4.67 gm/cc.
Fermion Index:
Fermion Index = 0.08 Boson Index = 0.92
Photoelectric:
PEGamagarite = 221.06 barns/electronU=PEGamagarite x r Electron Density= 918.50 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Gamagarite is Not Radioactive
Gamagarite Classification
Dana Class:
41.10.04.03 (41) Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen
(41.10) where (A++ B++)3 (XO4)2 Zq
(41.10.04) Goedkenite Group
41.10.04.01 Goedkenite (Sr,Ca)2Al(PO4)2(OH) P 21 /m 2/m
41.10.04.02 Bearthite Ca2Al(PO4)2(OH) P 21 /m 2/m
41.10.04.03 Gamagarite Ba2(Fe,Mn)(VO4)2(OH) P 21 /m 2/m
41.10.04.04 Tokyoite ! Ba2Mn(VO4)2(OH) P 21 /m 2/m
Strunz Class:
08.BG.05 08 - PHOSPHATES, ARSENATES, VANADATES
08.B - Phosphates, etc. with Additional Anions, without H2O
08.BG -With medium-sized and large cations, (OH, etc.):RO4 = 0.5:1
08.BG.05 Arsenbrackebuschite Pb2(Fe,Zn)(AsO4)2•(H2O) P 21 /m 2/m
08.BG.05 Bearthite Ca2Al(PO4)2(OH) P 21 /m 2/m
08.BG.05 Arsentsumebite Pb2Cu(AsO4)(SO4)(OH) P 21 /m 2/m
08.BG.05 Brackebuschite Pb2(Mn,Fe)(VO4)2(OH) P 21 /m 2/m
08.BG.05 Feinglosite ! Pb2(Zn,Fe)[(As,S)O4]2•(H2O) P 21 ,P 21 /m Mono
08.BG.05 Gamagarite Ba2(Fe,Mn)(VO4)2(OH) P 21 /m 2/m
08.BG.05 Goedkenite (Sr,Ca)2Al(PO4)2(OH) P 21 /m 2/m
08.BG.05 Tsumebite Pb2Cu(PO4)(SO4)(OH) P 21 /m 2/m
08.BG.05 Calderonite ! Pb2Fe(VO4)2(OH) P 21 /m 2/m
08.BG.05 Bushmakinite ! Pb2Al(PO4)(VO4)(OH) P 21 /m 2/m
08.BG.05 Tokyoite ! Ba2Mn(VO4)2(OH) P 21 /m 2/m
Other Gamagarite Information
References:
NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
See Also:
Links to other databases for Gamagarite :
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 Gamagarite Specimen Label here :
Gamagarite
Ba2(Fe+++,Mn+++)(VO4)2(OH)
Dana No: 41.10.04.03 Strunz No: 08.BG.05
Locality:
Notes:
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