Semenovite Mineral Data + Say SEMENOVITE

MineralsWeb Fine Minerals

General Semenovite Information

Help on Chemical  Formula: Chemical Formula: (Na,Ca)9(Ce,La)2(Fe++,Mn)(Si,Be)20(O,OH,F)48
Help on Composition: Composition: Molecular Weight = 1,853.28 gm
   Potassium         0.21 %  K     0.25 % K2O
   Sodium            8.31 %  Na   11.20 % Na2O
   Calcium           4.33 %  Ca    6.05 % CaO
   Lanthanum         6.00 %  La    7.03 % La2O3
   Cerium            5.29 %  Ce    6.20 % Ce2O3
   La,Ce,Pr,Nd,Sm,   3.11 %  RE    3.63 % REE2O3
   Yttrium           1.44 %  Y     1.83 % Y2O3
   Manganese         1.48 %  Mn    1.91 % MnO
   Beryllium         3.01 %  Be    8.37 % BeO
   Aluminum          0.44 %  Al    0.83 % Al2O3
   Zinc              0.35 %  Zn    0.44 % ZnO
   Iron              2.41 %   Fe    0.78 % FeO /  2.59 % Fe2O3
   Silicon          20.46 %  Si   43.77 % SiO2
   Hydrogen          0.22 %  H     1.94 % H2O
   Oxygen           38.33 %  O
   Fluorine          4.61 %  F     4.61 % F
                      -   %   F    -1.94 % -O=F2
                   ______        ______ 
                   100.00 %       99.48 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Na6.7Ca2K0.1La0.8Ce0.7Y0.3REE0.4Mn2+0.5Fe2+0.2Zn0.1Fe3+0.6Si13.5Be6.2 Al0.3O40.4F4.5(OH)4
Help on Environment: Environment: Occurs in border zone of the only epididymite-eudidymite bearing albitite, in cavities and fractures.
Help on IMA Status: IMA Status: Approved IMA 1972
Help on Locality: Locality: Ilimaussaq complex, South Greenland. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Yevgeny Ivanovich Semenov, (1951-), Russian mineralogist, IMGRE, Moscow, Russia.
 

Semenovite Image

Click Here for Larger Semenovite Image in a New Browser Window Images:
Click Here for Larger Semenovite Image

Semenovite

Comments: Tan crystals of semenovite to 1 mm across on matrix.
Location: Ilimaussaq, Tasseq, Greenland. Scale: Picture size 1 cm.
© John Veevaert

Semenovite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =1.0031:1:0.7186
Help on Cell Dimensions: Cell Dimensions: a = 13.879, b = 13.835, c = 9.942, Z = 2; V = 1,909.02 Den(Calc)= 3.22
Help on Crystal System: Crystal System: Orthorhombic - DipyramidalH-M Symbol (2/m 2/m 2/m) Space Group: Pmmn
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.73(1), 2.84(1), 3.28(1),
Click Here for Large Semenovite Structure Window Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate

Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above


Mazzi F , Ungaretti L , Dal Negro A , Petersen O V , Ronsbo J G , American Mineralogist , 64 (1979) p.202-210, The crystal structure of semenovite

 

Physical Properties of Semenovite

Help on Cleavage: Cleavage: None
Help on Color: Color: Brown, Orange brown, Gray, Reddish brown, Colorless.
Help on Density: Density: 3.14
Help on Diaphaniety: Diaphaniety: Transparent to translucent
Help on Fracture: Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Help on Habit: Habit: Pseudo Tetragonal - Crystals show a tetragonal shape.
Help on Habit: Habit: Twinning Common - Crystals are usually twinned.
Help on Hardness: Hardness: 3.5-4 - Copper Penny-Fluorite
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white
 

Optical Properties of Semenovite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.012 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.037 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1887,KPDmeas= 0.1935,KC= 0.1959
Help on Optical Data: Optical Data: Biaxial (-), a=1.595, b=1.614, g=1.614, bire=0.0190, 2V(Calc)=0, 2V(Meas)=0-55.
 

Calculated Properties of Semenovite

Help on Electron Density: Electron Density:

relectron=3.02 gm/cc
note: rSemenovite =3.14 gm/cc.

Help on Fermion Index Fermion Index Fermion Index = 0.04643
Boson Index = 0.95357
Help on Photoelectric: Photoelectric:

PESemenovite = 75.11 barns/electron
U=PESemenovite x relectron= 226.92 barns/cc.

Help on Radioactivity: Radioactivity:

GRapi = 14,789.78 (Gamma Ray American Petroleum Institute Units)

Semenovite is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.

Estimated Radioactivity from Semenovite - weak
Specimen
Size
Weight/Volume
(Sphere)
*
Calculated
Activity
Bequerols
(Bq)
Calculated
Activity
Curies (Ci)
Estimated
Activity
GR(api)
Estimated
Exposure
(mRem**)/hr
If Held in Hand
For One Hour
1000 gm / 8.47 cm 322,792 8.72E-06 14,789.78 4.86
100 gm / 3.93 cm 32,279 8.72E-07 1,478.98 0.49
10 gm / 1.83 cm 3,228 8.72E-08 147.90 0.05
1 gm / 8.47 mm 323 8.72E-09 14.79 0.00
0.1 gm / 3.93 mm 32 8.72E-10 1.48 0.00
0.01 gm / 1.83 mm 3 8.72E-11 0.15 0.00
0.001 gm / 0.85 mm 0 8.72E-12 0.01 0.00

Weight of pure Semenovite in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.14 gm/cc.*
Goverment Estimate of Average Annual Exposure ( 360 mRem) **
Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Estimated Thorium Activity ( 0.72 % Th) From Sum REE Elements (14.40 % REE)
 

Semenovite Classification

Help on  Dana Class: Dana Class: 72.5.2.4 (72)Phyllosilicate Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
  (72.5)with corrugated and complex layers
  (72.5.2)Leucospenite and related species
 
72.5.2.1 Leucosphenite Na4BaTi2O2[B2Si10O28] C 2/m 2/m
 
72.5.2.2 Nordite-(Ce) (Ce,La,Ca)(Sr,Ca)Na2(Na,Mn)(Zn,Mg)Si6O17 Pcca 2/m 2/m 2/m
 
72.5.2.3 Nordite-(La) (Na,Mn)3(Sr,Ca)(La,Ce)(Zn,Mg)Si6O17 Pcca 2/m 2/m 2/m
 
72.5.2.4 Semenovite (Na,Ca)9(Ce,La)2(Fe,Mn)(Si,Be)20(O,OH,F)48 Pmmn 2/m 2/m 2/m
 
72.5.2.5 Ferronordite-(Ce)! Na3SrCeFeSi6O17 Pcca 2/m 2/m 2/m
 
72.5.2.6 Manganonordite-(Ce)! Na3SrCeMnSi6O17 Pcca 2/m 2/m 2/m
 
72.5.2.7 Ferronordite-(La)! Na3Sr(La,Ce)FeSi6O17 Pcca 2/m 2/m 2/m
Help on  Strunz Class: Strunz Class: VIII/G.03-10 VIII - Silicates
  VIII/G - Intermediate between chain- and layered silicates
  VIII/G.03 - Semenovite-(Ce) - Nordite-(La) series
 
VIII/G.03-10 Semenovite (Na,Ca)9(Ce,La)2(Fe,Mn)(Si,Be)20(O,OH,F)48 Pmmn 2/m 2/m 2/m
 
VIII/G.03-20 Nordite-(Ce) (Ce,La,Ca)(Sr,Ca)Na2(Na,Mn)(Zn,Mg)Si6O17 Pcca 2/m 2/m 2/m
 
VIII/G.03-30 Nordite-(La) (Na,Mn)3(Sr,Ca)(La,Ce)(Zn,Mg)Si6O17 Pcca 2/m 2/m 2/m
 
VIII/G.03-40 Ferronordite-(Ce)! Na3SrCeFeSi6O17 Pcca 2/m 2/m 2/m
 
VIII/G.03-45 Ferronordite-(La)! Na3Sr(La,Ce)FeSi6O17 Pcca 2/m 2/m 2/m
 
VIII/G.03-50 Manganonordite-(Ce)! Na3SrCeMnSi6O17 Pcca 2/m 2/m 2/m
 

Other Semenovite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Dana8)
Help on See Also: See Also: Links to other databases for Semenovite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 -Google Images 4 -Google Scholar 5 -MinDAT 6 -MinMax(Deutsch) 7 -MinMax(English) 8 -Mineralienatlas (Deutsch) 9 -QUT Mineral Atlas 10 - WWW-MINCRYST

Search for Semenovite using:

Google
 
Web webmineral.com
[ALTAVISTA] [AOL] [All-The-Web] [HotBot] [Ixquick] [MAMMA] [MSN.COM] [Netscape] [Scirus] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Semenovite :

AA Mineral Specimens
B & L Fine Minerals
Crystal Vaults
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
Heliodor
John Betts Fine Minerals
Mason's Minerals
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz
T G Fine Minerals
Wrights Rock Shop

Translate Semenovite Mineral Data :

Ask about Semenovite 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 Semenovite Specimen Label here :

Semenovite

(Na,Ca)9(Ce,La)2(Fe++,Mn)(Si,Be)20(O,OH,F)48
Dana No: 72.5.2.4 Strunz No: VIII/G.03-10
Locality:

 

Notes:

 

 
   
 
Go To Webmineral Home Crystallography X-Ray D-Spacing Table Chemical Composition
Dana Classification Strunz Classification Table of Mineral Properties Alphabetical Listing of Minerals
Search Webmineral Photo Gallery of Mineral Images Help Files Links