Burangaite Mineral Data

General Burangaite Information

Chemical Formula:

(Na,Ca)2(Fe++,Mg)2Al10(PO4)8(OH,O)12•4(H2O)

Composition:

Molecular Weight = 738.18 gm

Sodium 2.18 % Na 2.94 % Na₂O

Calcium 1.63 % Ca 2.28 % CaO

Magnesium 1.32 % Mg 2.18 % MgO

Aluminum 18.28 % Al 34.53 % Al₂O₃

Iron 6.05 % Fe 6.81 % FeO / 1.08 % Fe₂O₃

Phosphorus 16.78 % P 38.46 % P₂O₅

Hydrogen 1.31 % H 11.71 % H₂O

Oxygen 52.45 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Na_0.7Ca_0.3Fe²⁺_0.7Mg_0.4Al₅Fe³⁺_0.1(PO₄)₄(OH)_5.6O_0.6ï¿½2(H₂O)

Environment:

Corroded aggregates with other phosphates in a zoned granite pegmatite.

IMA Status:

Approved IMA 1977

Locality:

Buranga pegmatite, near Gatumba, Rwanda. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Name Pronunciation:

Burangaite + Pronunciation

Synonym:

ICSD 84627

PDF 29-1190

Burangaite Image

Images:

Burangaite Gatumbaite

Comments: Small, blue burangaite crystals in beige gatumbaite.
Location: Horrsjoberg, Torby, VÃ¤rmland, Sweden. Scale: Micro-mount Size.
© Sonke Stolze / Systematic Minerals

Burangaite Crystallography

Axial Ratios:

a:b:c =4.9702:1:2.6644

Cell Dimensions:

a = 25.09, b = 5.048, c = 13.45, Z = 4; beta = 110.91° V = 1,591.31 Den(Calc)= 3.08

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/c

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

By Intensity(I/I_o): 11.71(1), 3.081(0.9), 3.115(0.7),

Physical Properties of Burangaite

Cleavage:

{100} Perfect

Color:

Blue, Greenish blue.

Density:

3.05

Diaphaneity:

Semitransparent

Habit:

Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).

Habit:

Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).

Hardness:

5 - Apatite

Streak:

light blue

Optical Properties of Burangaite

Gladstone-Dale:

CI meas= 0.029 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.039 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2044,KPDmeas= 0.2064,KC= 0.2126
Ncalc = 1.65

Optical Data:

Biaxial (-), a=1.611, b=1.635, g=1.643, bire=0.0320, 2V(Calc)=58, 2V(Meas)=58.

Pleochroism (x):

light blue.

Pleochroism (y):

dark blue.

Pleochroism (z):

colorless.

Calculated Properties of Burangaite

Electron Density:

Bulk Density (Electron Density)=3.04 gm/cc
note: Specific Gravity of Burangaite =3.05 gm/cc.

Fermion Index:

Fermion Index = 0.0028758519
Boson Index = 0.9971241481

Photoelectric:

PE_Burangaite= 3.39 barns/electron
U=PE_Burangaite x rElectron Density= 10.31 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Burangaite is Not Radioactive

Burangaite Classification

Dana Class:

42.09.01.01 (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen

(42.09)where (A)3 (XO4)2 Zq ï¿½ x(H2O)

(42.09.01)Burangaite Group

42.09.01.01 Burangaite (Na,Ca)2(Fe,Mg)2Al10(PO4)8(OH,O)12•4(H2O) C 2/c 2/m

42.09.01.02 Dufrenite FeFe4(PO4)3(OH)5•2(H2O) C 2/c 2/m

42.09.01.03 Natrodufrenite Na(Fe,Fe)(Fe,Al)5(PO4)4(OH)6•2(H2O) C 2/c 2/m

42.09.01.04 IMA2008-056! NaMnFe5(PO4)4(OH)6•2H2O C 2/c 2/m

42.09.01.05 Matioliite! NaMgAl5(PO4)4(OH)6•2H2O C 2/c 2/m

Strunz Class:

08.DK.15 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DK -With large and medium-sized cations, (OH, etc.):RO4 > 1:1 and < 2:1

08.DK.15 Dufrenite FeFe4(PO4)3(OH)5•2(H2O) C 2/c 2/m

08.DK.15 Burangaite (Na,Ca)2(Fe,Mg)2Al10(PO4)8(OH,O)12•4(H2O) C 2/c 2/m

08.DK.15 Natrodufrenite Na(Fe,Fe)(Fe,Al)5(PO4)4(OH)6•2(H2O) C 2/c 2/m

08.DK.15 Matioliite! NaMgAl5(PO4)4(OH)6•2H2O C 2/c 2/m

08.DK.15 IMA2008-056! NaMnFe5(PO4)4(OH)6•2H2O C 2/c 2/m

Other Burangaite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic4)

See Also:

Links to other databases for Burangaite :
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

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

Burangaite

(Na,Ca)2(Fe++,Mg)2Al10(PO4)8(OH,O)12•4(H2O)
Dana No: 42.09.01.01 Strunz No: 08.DK.15
Locality:

Notes:

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