Terskite Mineral Data

General Terskite Information

Chemical Formula:

Na4ZrSi6O15(OH)2•2(H2O)

Composition:

Molecular Weight = 646.98 gm

Sodium 14.11 % Na 19.02 % Na₂O

Zirconium 13.25 % Zr 17.90 % ZrO₂

Manganese 0.34 % Mn 0.44 % MnO

Silicon 26.31 % Si 56.28 % SiO₂

Hydrogen 0.71 % H 6.38 % H₂O

Oxygen 45.28 % O

______ ______

100.00 % 100.01 % = TOTAL OXIDE

Empirical Formula:

Na_3.97Mn²⁺_0.04Zr_0.94Si_6.06O_16.02•2.29(H₂O)

Environment:

In veins in pegmatites in alkalic massifs.

IMA Status:

Approved IMA 1983

Locality:

Mts. Alluaiv and Karnasurt, Lovozero massif, and on Mt. Rasvumchorr, Khibiny massif, Kola Peninsula, Russia. Link to MinDat.org Location Data.

Name Origin:

Named for the Tersk shore of the White Sea, southeastern Kola Peninsula, Russia.

Name Pronunciation:

Terskite

Synonym:

ICSD 39454

PDF 35-712

Terskite Image

Images:

Terskite

Comments: Pale violet terskite fragment.
Location: Mount Rasvumchorr, Khibiny Massif, Kola Peninsula, Murmansk District, Russia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Terskite Crystallography

Axial Ratios:

a:b:c =0.9623:1:0.5092

Cell Dimensions:

a = 14.195, b = 14.75, c = 7.511, Z = 4; V = 1,572.63 Den(Calc)= 2.73

Crystal System:

Orthorhombic - Pyramidal H-M Symbol (mm2) Space Group: Pnc2

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

By Intensity(I/I_o): 3.257(1), 3.299(1), 3.324(1),

Physical Properties of Terskite

Color:

White, Light lilac.

Density:

2.71

Habit:

Pseudo Tetragonal - Crystals show a tetragonal shape.

Hardness:

5 - Apatite

Luminescence:

Fluorescent, Short UV=yellow-white, Long UV=yellow-white.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Terskite

Gladstone-Dale:

CI meas= -0.004 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.004 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2127,KPDmeas= 0.2143,KC= 0.2135
Ncalc = 1.58

Optical Data:

Biaxial (-), a=1.576, b=1.582, g=1.584, bire=0.0080

Pleochroism (x):

colorless.

Pleochroism (y):

colorless.

Pleochroism (z):

colorless.

Calculated Properties of Terskite

Electron Density:

Bulk Density (Electron Density)=2.69 gm/cc
note: Specific Gravity of Terskite =2.73 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Terskite= 18.67 barns/electron
U=PE_Terskite x rElectron Density= 50.12 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Terskite is Not Radioactive

Terskite Classification

Dana Class:

78.07.15.01 (78)Unclassified silicates

(78.07)wholly unclassified silicates

(78.07.15)Dana Group

78.07.15.01 Terskite Na4ZrSi6O15(OH)2•2(H2O) Pnc2 mm2

Strunz Class:

09.DM.40 09 - SILICATES (Germanates)

09.D - Inosilicates* Structural terminology according to Liebau (1985)

09.DM -Inosilicates with 6-periodic single chains

09.DM.40 Terskite Na4ZrSi6O15(OH)2•2(H2O) Pnc2 mm2

Other Terskite Information

References:

NAME( AntBidBlaNic2) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990;www.saint-hilaire.ca) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Terskite :
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
17 - WWW-MINCRYST

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

Terskite

Na4ZrSi6O15(OH)2•2(H2O)
Dana No: 78.07.15.01 Strunz No: 09.DM.40
Locality:

Notes:

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