General Roedderite Information Chemical Formula: |
(Na,K)2(Mg,Fe++)5Si12O30 |
Composition: |
Molecular Weight = 1,031.99 gm |
|
Potassium 1.89 % K 2.28 % K2O |
|
Sodium 3.34 % Na 4.50 % Na2O |
|
Magnesium 8.83 % Mg 14.65 % MgO |
|
Iron 6.76 % Fe 8.70 % FeO |
|
Silicon 32.66 % Si 69.87 % SiO2 |
|
Oxygen 46.51 % O |
|
______ ______ |
|
100.00 % 100.00 % = TOTAL OXIDE |
Empirical Formula: |
Na1.5K0.5Mg3.75Fe2+1.25Si12O30 |
Environment: |
In vesicles in contact metamorphosed basement gneiss xenoliths in leucite tephrite (Bellerberg volcano, Germany); an accessory mineral in an enstatite chondrite (Indarch meteorite). Forms a series with eifelite. |
IMA Status: |
Approved IMA 1966 |
Locality: |
In the Indarch, Witchita County, and Canyon Diablo meteorites. Link to MinDat.org Location Data. |
Name Origin: |
Named for Edwin Woods Roedder (1919- ), mineralogist, U.S. Geological Survey, who noted the synthetic compound. |
Name Pronunciation: |
Roedderite + Pronunciation |
Synonym: |
ICSD 68545 |
|
PDF 23-76 |
| | Roedderite Image
Images:
|
|
Roedderite Crystallography Axial Ratios: |
a:c = 1:1.40792 |
Cell Dimensions: |
a = 10.139, c = 14.275, Z = 2; V = 1,270.86 Den(Calc)= 2.70 |
Crystal System: |
Hexagonal - Dihexagonal DipyramidalH-M Symbol (6/m 2/m 2/m) Space Group: P 63/mmc |
X Ray Diffraction: |
By Intensity(I/Io): 3.57(1), 3.239(0.77), 2.922(0.67), |
Crystal Structure:
|
Mouse
|
| Physical Properties of Roedderite Cleavage: |
None |
Color: |
Blue green, Colorless, Yellow, Reddish brown. |
Density: |
2.6 |
Diaphaneity: |
Transparent |
Hardness: |
5-6 - Between Apatite and Orthoclase |
Luster: |
Vitreous (Glassy) |
Streak: |
white |
| Optical Properties of Roedderite Gladstone-Dale: |
CI meas= -0.017 (Superior) - where the CI = (1-KPDmeas/KC) |
CI calc= 0.021 (Excellent) - where the CI = (1-KPDcalc/KC) KPDcalc= 0.1998,KPDmeas= 0.2075,KC= 0.204 Ncalc = 1.53 - 1.55 Optical Data: |
Uniaxial (+), w=1.537, e=1.542, bire=0.0050. |
| Calculated Properties of Roedderite Electron Density: |
Bulk Density (Electron Density)=2.58 gm/cc |
note: Specific Gravity of Roedderite =2.60 gm/cc. Fermion Index: |
Fermion Index = 0.02 |
Boson Index = 0.98 Photoelectric: |
PERoedderite = 3.68 barns/electron |
U=PERoedderite x relectron= 9.48 barns/cc. Radioactivity: |
|
GRapi = 27.10 (Gamma Ray American Petroleum Institute Units)
Estimated Radioactivity from Roedderite - barely detectable | Roedderite Classification Dana Class: |
63.02.01a.14 (63)Cyclosilicate Condensed Rings |
|
(63.02)6-membered rings |
|
(63.02.01a)Milarite - Osumilite group (Milarite - Osumilite subgroup) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Strunz Class: |
09.CM.05 09 - SILICATES (Germanates) |
|
09.C - Cyclosilicates |
|
09.CM -[Si6O18]12- 6-membered double rings (sechser-Doppelringe) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other Roedderite Information References: |
NAME( AntBidBlaNic2) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990) |
See Also: |
Links to other databases for Roedderite : |
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 Roedderite using: Visit our Advertisers for Roedderite : A Bijoux Google Search for RoedderiteAdam's Minerals Google Search for Roedderite Cape Minerals Google Search for Roedderite Dakota Matrix Minerals Google Search for Roedderite Excalibur Mineral Corp. Google Search for Roedderite Exceptional Minerals Google Search for Roedderite John Betts Fine Minerals Search for Roedderite McDougall Minerals Google Search for Roedderite Mineral News Website Link Rock and Mineral Shows Google Search for Roedderite Weinrich Minerals, Inc. Google Search for Roedderite Ask about Roedderite here : Print or Cut-and-Paste your Roedderite Specimen Label here :
| |
|
| |