General Mathiasite Information Chemical Formula: |
(K,Ca,Sr)(Ti,Cr,Fe,Mg)21O38 |
Composition: |
Molecular Weight = 1,682.56 gm |
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Potassium 1.39 % K 1.68 % K2O |
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Strontium 0.52 % Sr 0.62 % SrO |
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Calcium 0.71 % Ca 1.00 % CaO |
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Magnesium 0.72 % Mg 1.20 % MgO |
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Titanium 36.99 % Ti 61.72 % TiO2 |
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Chromium 18.54 % Cr 24.25 % CrO |
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Iron 4.98 % Fe 6.41 % FeO |
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Oxygen 36.13 % O |
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______ ______ |
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100.00 % 96.86 % = TOTAL OXIDE |
Empirical Formula: |
K0.6Ca0.3Sr0.1Ti13Cr6Fe2+1.5Mg0.5O38 |
Environment: |
In kimberlite. |
IMA Status: |
Approved IMA 1983 |
Locality: |
Jagersfontein mine, Orange Free State, South Africa. Link to MinDat.org Location Data. |
Name Origin: |
Named for Frances Celia Morna Mathias (1913-), British-South African geochemist, University of Capetown, South Africa. |
Name Pronunciation: |
Mathiasite + Pronunciation |
Synonym: |
ICSD 35353 |
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PDF 46-1468 |
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Images:
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Mathiasite Crystallography Axial Ratios: |
a:c = 1:1.99324 |
Cell Dimensions: |
a = 10.36, c = 20.65, Z = 3; V = 1,919.42 Den(Calc)= 4.37 |
Crystal System: |
Trigonal - RhombohedralH-M Symbol ( 3) Space Group: R 3 |
X Ray Diffraction: |
By Intensity(I/Io): 1.44(1), 2.14(1), 2.25(0.9), |
Crystal Structure:
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Mouse
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| Physical Properties of Mathiasite Cleavage: |
None |
Color: |
Black. |
Density: |
4.6 |
Diaphaneity: |
Opaque |
Fracture: |
Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz). |
Hardness: |
7.5 - Garnet |
Luster: |
Metallic |
Streak: |
gray |
| Optical Properties of Mathiasite Dichroism (e): |
dark tan. |
Dichroism (w): |
weaker dark tan. |
Optical Data: |
Uniaxial (?). |
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NCalc= 2.36 - from Gladstone-Dale relationship (KC = 0.3122) where Ncalc=Dcalc*KC+1 |
NCalc= 2.44 - from Gladstone-Dale relationship (KC = 0.3122) where Ncalc=Dmeas*KC+1 RL Anisotrophism: |
Moderate, brownish tan to dark brown. |
RL Color: |
Tan. |
Reflectivity |
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| Calculated Properties of Mathiasite Electron Density: |
Bulk Density (Electron Density)=4.16 gm/cc |
note: Specific Gravity of Mathiasite =4.37 gm/cc. Fermion Index: |
Fermion Index = 0.06 |
Boson Index = 0.94 Photoelectric: |
PEMathiasite = 12.77 barns/electron |
U=PEMathiasite x relectron= 53.09 barns/cc. Radioactivity: |
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GRapi = 19.11 (Gamma Ray American Petroleum Institute Units)
Estimated Radioactivity from Mathiasite - barely detectable | Mathiasite Classification Dana Class: |
08.05.01.07 (08)Multiple Oxides with Nb, Ta, and Ti |
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(08.05)Dana Type |
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(08.05.01)Crichtonite group (ABC18 T2 O38) |
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Strunz Class: |
04.CC.40 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate |
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04.C - Metal:Oxygen = 2:3, 3:5, and Similar |
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04.CC -With large and medium-sized cations |
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| Other Mathiasite Information References: |
NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic3) |
See Also: |
Links to other databases for Mathiasite : |
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 Search for Mathiasite using: Visit our Advertisers for Mathiasite : A Bijoux Google Search for MathiasiteAdam's Minerals Google Search for Mathiasite Cape Minerals Google Search for Mathiasite Dakota Matrix Minerals Google Search for Mathiasite Excalibur Mineral Corp. Google Search for Mathiasite Exceptional Minerals Google Search for Mathiasite John Betts Fine Minerals Search for Mathiasite McDougall Minerals Google Search for Mathiasite Mineral News Website Link Rock and Mineral Shows Google Search for Mathiasite Weinrich Minerals, Inc. Google Search for Mathiasite Ask about Mathiasite here : Print or Cut-and-Paste your Mathiasite Specimen Label here :
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