|
|
Boromullite Mineral Data
|
|
|
General Boromullite Information
|
Chemical Formula: |
Al4.5SiB0.5O9.5 |
Composition: |
Molecular Weight = 610.43 gm |
|
Magnesium 0.04 % Mg 0.07 % MgO |
|
Aluminum 39.25 % Al 74.16 % Al2O3 |
|
Iron 0.27 % Fe 0.35 % FeO |
|
Silicon 8.88 % Si 19.00 % SiO2 |
|
Boron 2.02 % B 6.50 % B2O3 |
|
Oxygen 49.54 % O |
|
______ ______ |
|
100.00 % 100.08 % = TOTAL OXIDE |
Empirical Formula: |
Mg0.01Fe2+0.03Al8.88Si1.93B1.14O18.9 |
Environment: |
Formed during anatexis of B-rich pelitic rocks under granulite facies conditions. Structurally related to mullite. |
IMA Status: |
Approved IMA 2007 (Dana # Added) |
Locality: |
Mount Stafford, Northern Territory, Australia Link to MinDat.org Location Data. |
Name Origin: |
Named as the boron analog to mullite. |
Synonym: |
IMA2007-021 |
|
Boromullite Image |
Images:
|
|
Boromullite
Comments: PPL image of holotype boromullite prism in thin section 2006-MST22a. Bmu = boromullite, Crd = cordierite, Hc = hercynite, Kfs = K-feldspar, Sil = sillimanite. Eur. J. Mineral v20:935.
Location: Mount Stafford, central Australia.
Scale: See Image.
© Eur. J. Mineral |
|
Images:
|
|
Boromullite
Comments: BSE image of holotype boromullite prism in thin section 2006-MST22a. Bmu = boromullite, Crd = cordierite, Hc = hercynite, Kfs = K-feldspar, Sil = sillimanite. Eur. J. Mineral v20:935.
Location: Mount Stafford, central Australia.
Scale: See Image.
© Eur. J. Mineral |
|
Boromullite Crystallography
|
Axial Ratios: |
a:b:c =0.3805:1:0.5108 |
Cell Dimensions: |
a = 5.7168, b = 15.023, c = 7.675, Z = 2; V = 659.16 Den(Calc)= 3.08 |
Crystal System: |
Orthorhombic - Pyramidal H-M Symbol (mm2) Space Group: C mc21 |
X Ray Diffraction: |
By Intensity(I/Io): 3.38(1), 1.512(0.8), 2.19(0.8),2.51(0.6), 2.67(0.6), 2.11(0.5), 5.37(0.5), 1.682(0.3), |
|
Physical Properties of Boromullite
|
Cleavage: |
None |
Color: |
White. |
Diaphaneity: |
Transparent |
Habit: |
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline). |
Luster: |
Vitreous (Glassy) |
Streak: |
white |
|
Optical Properties of Boromullite
|
Gladstone-Dale: |
CI calc= 0.005 (Superior) - where the CI = (1-KPDcalc/KC) KPDcalc= 0.2067,KC= 0.2078 Ncalc = 1.64 |
Optical Data: |
Biaxial (+), a=1.627, b=1.634, g=1.649, bire=0.0220 |
|
Calculated Properties of Boromullite
|
Electron Density: |
Bulk Density (Electron Density)=3.03 gm/cc note: Specific Gravity of Boromullite =3.08 gm/cc. |
Fermion Index: |
Fermion Index = 0.008500053 Boson Index = 0.991499947 |
Photoelectric: |
PEBoromullite = 1.59 barns/electron U=PEBoromullite x rElectron Density= 4.82 barns/cc. |
Radioactivity: |
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Boromullite is Not Radioactive |
|
Boromullite Classification
|
Dana Class: |
52.02.02a.03 (52)Nesosilicate Insular SiO4 Groups and O, OH, F, and H2O |
|
(52.02)with cations in [4] and >[4] coordination |
|
(52.02.02a)Al2SiO5 (Sillimanite subgroup) |
|
52.02.02a.01 Sillimanite Al2SiO5=Al[6]Al[4]OSiO4 P nma 2/m 2/m 2/m |
|
52.02.02a.02 Mullite Al(42x)Si(2-2x)O(10-x)wherex=0.17to0.59 Pbam 2/m 2/m 2/m |
|
52.02.02a.03 Boromullite! Al4.5SiB0.5O9.5 C mc21 mm2 |
Strunz Class: |
09.AF.23 09 - SILICATES (Germanates) |
|
09.A - Nesosilicates |
|
09.AF -Nesosilicates with additional anions; |
|
09.AF.23 Boromullite! Al4.5SiB0.5O9.5 C mc21 mm2 |
|
Other Boromullite Information
|
References: |
NAME( AmMin, v94:648) PHYS. PROP.(AmMin, v94:648) OPTIC PROP.(AmMin, v94:648) |
See Also: |
Links to other databases for Boromullite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info
Search for Boromullite using:
[AOL]
[Bing]
[Dog Pile]
[GeoScienceWorld]
[HotBot]
[Ixquick]
[Lycos]
[MAMMA]
[Scirus]
[Teoma]
[WebCrawler]
[Wikipedia]
[YAHOO]
Visit our Advertisers for Boromullite :
Ask about Boromullite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in
Espaņol
Print or Cut-and-Paste your Boromullite Specimen Label here :
Boromullite
Al4.5SiB0.5O9.5
Dana No: 52.02.02a.03 Strunz No: 09.AF.23
Locality:
Notes:
|
|
|
|
|
|
Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.