Sigismundite Mineral Data

Sigismundite Mineral Data +

[New Updates] [Gallery 1] [Gallery 2] [Gallery 3] [Rock Shop Gallery]
Serving the mineral collector and educator community since 1970
Over 900,000 mineral specimens in stock
New minerals acquired weekly - Wright's Rock Shop

General Sigismundite Information

Chemical Formula:

(Ba,K,Pb)Na3(Ca,Sr)(Fe++,Mg,Mn)14Al(OH)2(PO4)12

Composition:

Molecular Weight = 2,242.07 gm

Potassium 0.17 % K 0.21 % K₂O

Barium 4.90 % Ba 5.47 % BaO

Sodium 3.08 % Na 4.15 % Na₂O

Strontium 0.78 % Sr 0.92 % SrO

Calcium 1.43 % Ca 2.00 % CaO

Magnesium 6.18 % Mg 10.25 % MgO

Manganese 0.49 % Mn 0.63 % MnO

Aluminum 1.20 % Al 2.27 % Al₂O₃

Iron 20.18 % Fe 25.96 % FeO

Phosphorus 16.58 % P 37.99 % P₂O₅

Hydrogen 0.09 % H 0.80 % H₂O

Lead 9.24 % Pb 9.96 % PbO

Oxygen 35.68 % O

______ ______

100.00 % 100.61 % = TOTAL OXIDE

Empirical Formula:

Na₃Ba_0.8K_0.1PbCa_0.8Sr_0.2Fe²⁺_8.1Mg_5.7Mn²⁺_0.2Al(PO₄)₁₂(OH)₂

Environment:

In a phengitic quartzite.

IMA Status:

Approved IMA 1996 (Dana # Added)

Locality:

Near Madesimo, Spluga Valley, Central Alps, Italy. Link to MinDat.org Location Data.

Name Origin:

For Pietro Sigismund (1874-1962), a well known collector of minerals from Valtellina, especially Val Malenco.

Synonym:

ICSD 82491

IMA1994-033

PDF 86-1397

Search for Sigismundite Images

Images:

Image not yet available on Webmineral.com

Try searching images.google.com or Mindat Picture Gallary for mineral pictures. Caution: The images retrieved may not be appropriate.

Sigismundite Crystallography

Axial Ratios:

a:b:c =1.6506:1:2.4604

Cell Dimensions:

a = 16.394, b = 9.932, c = 24.437, Z = 4; beta = 105.78° V = 3,829.00 Den(Calc)= 3.89

Crystal System:

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

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

By Intensity(I/I_o): 3.01(1), 3.181(0.51), 2.678(0.42),

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

Demartin F , Gramaccioli C M , Pilati T , Sciesa E , The Canadian Mineralogist , 34 (1996) p.827-834, Sigismundite, (Ba,K,Pb)Na3(Ca,Sr)(Fe,Mg,Mn)14Al(OH)2(PO4)12, a new, Ba-rich member of the arrojadite group from Spluga Valley, Italy, Locality: Spluga Valley, Italy

Physical Properties of Sigismundite

Cleavage:

[???] Perfect

Color:

Grayish green.

Density:

3.54

Diaphaniety:

Translucent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Habit:

Aggregates - Made of numerous individual crystals or clusters.

Luster:

Greasy (Oily)

Streak:

white

Optical Properties of Sigismundite

Gladstone-Dale:

CI meas= -0.011 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.08 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1671,KPDmeas= 0.1836,KC= 0.1816

Optical Data:

Biaxial (+/-), b=1.65

Calculated Properties of Sigismundite

Electron Density:

r_electron=3.36 gm/cc
note: r_Sigismundite=3.54 gm/cc.

Fermion Index

Fermion Index = 0.04035
Boson Index = 0.95965

Photoelectric:

PE_Sigismundite= 178.53 barns/electron
U=PE_Sigismundite x r_electron= 600.02 barns/cc.

Radioactivity:

GRapi = 2.40 (Gamma Ray American Petroleum Institute Units)

Estimated Radioactivity from Sigismundite - barely detectable

Sigismundite Classification

Dana Class:

41.7.3.1 (41)Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen

(41.7)where (A B)m (XO4)4 Zq

(41.7.3)Dana Group

41.7.3.1 Sigismundite ! (Ba,K,Pb)Na3(Ca,Sr)(Fe,Mg,Mn)14Al(OH)2(PO4)12 C 2/c 2/m

Strunz Class:

VII/B.20-25 VII - Phosphates, Arsenates and Vanadates

VII/B - Waterfree phosphates with unfamiliar anions F, Cl, O, OH. cations of medium and big size: Mg, Cu, Zn, and Ca, Na, K, Ba, Pb

VII/B.20 - Arrojadite - Samuelsonite series

VII/B.20-10 Arrojadite KNa4CaMn4Fe10Al(PO4)12(OH,F)2 C 2/c 2/m

VII/B.20-20 Dickinsonite KNa4Ca(Mn,Fe)14Al(PO4)12(OH)2 C 2/c 2/m

VII/B.20-25 Sigismundite (Ba,K,Pb)Na3(Ca,Sr)(Fe,Mg,Mn)14Al(OH)2(PO4)12 C 2/c 2/m

VII/B.20-30 Samuelsonite (Ca,Ba)Ca8(Fe,Mn)4Al2(PO4)10(OH)2 C 2/m 2/m

VII/B.20-40 Nabiasite! BaMn9[(V,As)O4]6(OH)2 P a3 2/m 3

Other Sigismundite Information

References:

NAME( MinRec, Vol. 28, No. 3) PHYS. PROP.(Am.Min.,Vol.82,p432,1997) OPTIC PROP.(Am.Min.,Vol.82,p432,1997)

See Also:

Links to other databases for Sigismundite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 -Google Images 4 -Google Scholar 5 -Handbook of Mineralogy (UofA) 6 -MinDAT 7 -MinMax(Deutsch) 8 -MinMax(English) 9 -Mineralienatlas (Deutsch) 10 -QUT Mineral Atlas

Search for Sigismundite using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Sigismundite :
AA Mineral Specimens
B and L Minerals
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Minernet.it
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Sigismundite Mineral Data :

Ask about Sigismundite 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 Español

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

Sigismundite

(Ba,K,Pb)Na3(Ca,Sr)(Fe++,Mg,Mn)14Al(OH)2(PO4)12
Dana No: 41.7.3.1 Strunz No: VII/B.20-25
Locality:

Notes: