Lalondeite Mineral Data

General Lalondeite Information

Chemical Formula:

(Na,Ca)6(Ca,Na)3Si16O38(F,OH)2•3(H2O)

Composition:

Molecular Weight = 1,441.00 gm

Potassium 0.60 % K 0.72 % K₂O

Sodium 8.50 % Na 11.46 % Na₂O

Calcium 10.87 % Ca 15.22 % CaO

Silicon 31.50 % Si 67.38 % SiO₂

Hydrogen 0.49 % H 4.34 % H₂O

Chlorine 0.17 % Cl 0.17 % Cl

- % Cl -0.04 % -O=Cl₂

Oxygen 46.57 % O

Fluorine 1.31 % F 1.31 % F

- % F -0.55 % -O=F₂

______ ______

100.00 % 100.01 % = TOTAL OXIDE

Empirical Formula:

Na_5.33Ca_0.91K_0.22Ca₃Si_16.16O₃₈F_0.99(OH)_0.94Cl_0.07ï¿½3(H₂O)

Environment:

Discovered on a single, handsized sample of altered breccia (or possibly, altered marble) collected in the summer of 1985. Reyerite group; structure determined.

IMA Status:

Approved IMA 2002 (Dana # Added)

Locality:

Poudrette quarry, Mont Saint-Hilaire, Rouville County, Quebec, Canada. Link to MinDat.org Location Data.

Name Origin:

Named for Andre Edmond Lalonde (b. 1955), Professor of Geology at the University of Ottawa, Ottawa, Ontario, Canada.

Synonym:

IMA2002-026

Lalondeite Image

Images:

Lalondeite

Comments: Vein of pinkish lalondeite with a greenish clinoamphibole in altered breccia.
Location: Poudrette quarry, Mont Saint-Hilaire, Rouville County, Quebec, Canada. Scale: Picture size 3 cm.
© Canadian Mineralogist

Lalondeite Crystallography

Axial Ratios:

a:b:c =0.9975:1:1.2602

Cell Dimensions:

a = 9.589, b = 9.613, c = 12.115, Z = 1; alpha = 96.62°, beta = 92.95°, gamma = 119.81° V = 961.24 Den(Calc)= 2.49

Crystal System:

Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1

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

By Intensity(I/I_o): 2.888(1)(123), 11.938(0.9)(001), 2.967(0.5)(122),3.972(0.4)(003), 2.981(0.35)(213), 4.106(0.3)(020), 4.142(0.3)(220),

Physical Properties of Lalondeite

Cleavage:

{001} Perfect

Color:

Pink.

Density:

2.5

Diaphaneity:

Transparent

Fracture:

Brittle - Splintery - Brittle fracture leaving splintery fragments.

Habit:

Irregular Grains - Occurs as splotchy, anhedral crystals forming inclusions in other minerals or rocks.

Habit:

Subhedral Crystals - Occurs as crystals which tend to exhibit a recognizable crystal shape.

Hardness:

3 - Calcite

Luminescence:

Fluorescent, Short UV=violet-blue, Long UV=none.

Luster:

Pearly

Streak:

white

Optical Properties of Lalondeite

Gladstone-Dale:

CI meas= 0.003 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.007 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2097,KPDmeas= 0.2105,KC= 0.2112
Ncalc = 1.53

Optical Data:

Biaxial (-), a=1.522, b=1.528, g=1.529, bire=0.0070, 2V(Calc)=44, 2V(Meas)=48. Dispersion dispersion not observed.

Calculated Properties of Lalondeite

Electron Density:

Bulk Density (Electron Density)=2.50 gm/cc
note: Specific Gravity of Lalondeite =2.50 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_Lalondeite= 2.76 barns/electron
U=PE_Lalondeite x r_electron= 6.90 barns/cc.

Radioactivity:

GRapi = 8.61 (Gamma Ray American Petroleum Institute Units)
Concentration of Lalondeite per GRapi unit = 11.61 (%)

Estimated Radioactivity from Lalondeite - barely detectable

Lalondeite Classification

Dana Class:

73.02.02d.02 (73)Phyllosilicate Condensed Tetrahedral Sheets

(73.02)with double and single layers

(73.02.02d)Reyerite group (Triclinic Subgroup)

73.02.02d.01 Martinite! (Na,[],Ca)12Ca4(Si,S,B)14B2O38(OH,Cl)2F2•4(H2O) P1 1

73.02.02d.02 Lalondeite! (Na,Ca)6(Ca,Na)3Si16O38(F,OH)2•3(H2O) P1 1

Strunz Class:

09.EE.85 09 - SILICATES (Germanates)

09.E - Phyllosilicates

09.EE -Single tetrahedral nets of 6-membered rings

09.EE.85 Lalondeite! (Na,Ca)6(Ca,Na)3Si16O38(F,OH)2•3(H2O) P1 1

Other Lalondeite Information

References:

NAME( CanMin v43:181) PHYS. PROP.(CanMin v43:181) OPTIC PROP.(CanMin v43:181)

See Also:

Links to other databases for Lalondeite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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

Lalondeite

(Na,Ca)6(Ca,Na)3Si16O38(F,OH)2•3(H2O)
Dana No: 73.02.02d.02 Strunz No: 09.EE.85
Locality:

Notes:

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