Yofortierite Mineral Data
General Yofortierite Information
Chemical Formula:
(Mn,Mg)5Si8O20(OH)2•8-9(H2O)
Composition:
Molecular Weight = 1,002.61 gm
Calcium 0.80 % Ca 1.12 % CaO
Magnesium 1.45 % Mg 2.41 % MgO
Manganese 21.92 % Mn 28.30 % MnO
Aluminum 0.81 % Al 1.53 % Al2 O3
Zinc 0.65 % Zn 0.81 % ZnO
Silicon 22.41 % Si 47.94 % SiO2
Hydrogen 2.01 % H 17.97 % H2 O
Oxygen 49.95 % O
______ ______
100.00 % 100.08 % = TOTAL OXIDE
Empirical Formula:
Mn2+ 4 Mg0.6 Al0.3 Ca0.2 Zn0.1 Si8 O20.3 (OH)2 �9(H2 O)
Environment:
Late stage hydrothermal mineral in pegmatite veins within nepheline syenite.
IMA Status:
Approved IMA 1975
Locality:
Mont Saint-Hilaire, Quebec, Canada. Link to MinDat.org Location Data.
Name Origin:
Named for Yves Oscar Fortier (1914-), formater Director of the Geological Survey of Canada (1964-1972).
Synonym:
IMA1974-045
Mn-palygorskite
Sepiolite - Mn bearing
Yofortierite Image
Images:
Yofortierite
Comments: Radial spray of yofortierite in matrix.
Location: Mt. St. Hilaire, Quebec, Canada.
Scale: Picture size 1.5 cm.
© John Veevaert
Yofortierite Crystallography
Axial Ratios:
a:b:c =0.6945:1:0.2735
Cell Dimensions:
a = 12.759, b = 18.369, c = 5.024, Z = 2; beta = 94.98° V = 1,173.03 Den(Calc)= 2.84
Crystal System:
Monoclinic - Domatic H-M Symbol (m) Space Group: Pn(?)
X Ray Diffraction:
By Intensity(I/Io ): 10.5(1), 3.302(0.9), 2.621(0.3),
Physical Properties of Yofortierite
Color:
Violet brown, Light violet, Pink.
Density:
2.18
Diaphaneity:
Transparent
Fracture:
Elastic - Fragments which spring back after bending.
Habit:
Acicular - Occurs as needle-like crystals.
Habit:
Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)
Hardness:
2.5 - Finger Nail
Streak:
light pink
Optical Properties of Yofortierite
Gladstone-Dale:
CI meas = -0.095 (Poor) - where the CI = (1-KPDmeas /KC ) CI calc = 0.16 (Poor) - where the CI = (1-KPDcalc /KC )
KPDcalc = 0.1917,KPDmeas = 0.2498,KC = 0.2282 Ncalc = 1.5 - 1.65
Optical Data:
Biaxial (?), a=1.53, g=1.559, bire=0.0290
Pleochroism (x):
distinct.
Pleochroism (y):
distinct.
Pleochroism (z):
distinct.
Calculated Properties of Yofortierite
Electron Density:
Bulk Density (Electron Density)=2.18 gm/cc note: Specific Gravity of Yofortierite =2.18 gm/cc.
Fermion Index:
Fermion Index = 0.01 Boson Index = 0.99
Photoelectric:
PEYofortierite = 6.81 barns/electronU=PEYofortierite x r Electron Density= 14.82 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Yofortierite is Not Radioactive
Yofortierite Classification
Dana Class:
74.03.01a.03 (74) Phyllosilicate Modulated Layers
(74.03) with joined strips
(74.03.01a) Palygorskite-sepiolite group (Palygorskite subgroup)
74.03.01a.01 Palygorskite (Mg,Al)2Si4O10(OH)•4(H2O) C 2/m 2/m
74.03.01a.02 Tuperssuatsiaite Na(Fe,Mn)3[Si8O20](OH)2•n(H2O) C 2/m Mono
74.03.01a.03 Yofortierite (Mn,Mg)5Si8O20(OH)2•8-9(H2O) Pn(?) m
74.03.01a.04 Kalifersite ! (K,Na)5Fe7Si20O50(OH)6•12(H2O) P1 1
Strunz Class:
09.EE.20 09 - SILICATES (Germanates)
09.E - Phyllosilicates
09.EE -Single tetrahedral nets of 6-membered rings
09.EE.20 Palygorskite (Mg,Al)2Si4O10(OH)•4(H2O) C 2/m 2/m
09.EE.20 Yofortierite (Mn,Mg)5Si8O20(OH)2•8-9(H2O) Pn(?) m
09.EE.20 Tuperssuatsiaite Na(Fe,Mn)3[Si8O20](OH)2•n(H2O) C 2/m Mono
Other Yofortierite 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 Yofortierite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - GeoScienceWorld
8 - Google Images
9 - Google Scholar
10 - Handbook of Mineralogy (MinSocAm)
11 - Handbook of Mineralogy (UofA)
12 - MinDAT
13 - Mineralienatlas (Deutsch)
14 - Online Mineral Museum
15 - QUT Mineral Atlas
16 - Ruff.Info
Search for Yofortierite using:
[AOL ]
[Bing ]
[Dog Pile ]
[GeoScienceWorld ]
[HotBot ]
[Ixquick ]
[Lycos ]
[MAMMA ]
[Scirus ]
[Teoma ]
[WebCrawler ]
[Wikipedia ]
[YAHOO ]
Visit our Advertisers for Yofortierite :
Ask about Yofortierite 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 Yofortierite Specimen Label here :
Yofortierite
(Mn,Mg)5Si8O20(OH)2•8-9(H2O)
Dana No: 74.03.01a.03 Strunz No: 09.EE.20
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.