Niocalite Mineral Data

General Niocalite Information

Chemical Formula:

Ca14Nb2(Si2O7)4O6F2

Composition:

Molecular Weight = 1,553.57 gm

Calcium 36.12 % Ca 50.53 % CaO

Niobium 11.96 % Nb 17.11 % Nb₂O₅

Silicon 14.46 % Si 30.94 % SiO₂

Oxygen 35.01 % O

Fluorine 2.45 % F 2.45 % F

- % F -1.03 % -O=F₂

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ca₁₄Nb₂(Si₂O₇)₄O₆F₂

Environment:

In carbonatites.

IMA Status:

Valid Species (Pre-IMA) 1956

Locality:

Oka, Quebec, Canada. Link to MinDat.org Location Data.

Name Origin:

Named for its composition (Niobium, Calcium).

Name Pronunciation:

Niocalite + Pronunciation

Synonym:

ICSD 31269

PDF 11-633

Niocalite Image

Images:

Niocalite

Comments: Yellowish brown crystal prisms of niocalite in a carbonatite rock matrix.
Location: Oka, Oka complex, Deux-Montagnes Co., Québec, Canada. Scale: Crystal length 1 cm.
© Jeff Weissman / Photographic Guide to Mineral Species

Niocalite Crystallography

Axial Ratios:

a:b:c =1.0414:1:0.7065

Cell Dimensions:

a = 10.863, b = 10.431, c = 7.37, Z = 1; beta = 110.1° V = 784.25 Den(Calc)= 3.29

Crystal System:

Monoclinic - Domatic H-M Symbol (m) Space Group: Pa

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

By Intensity(I/I_o): 3.01(1), 2.85(0.6), 2.89(0.6),

Physical Properties of Niocalite

Cleavage:

None

Color:

Light yellow.

Density:

3.32

Diaphaneity:

Transparent

Fracture:

Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.

Habit:

Square - Occurs as square crystals in shape or outline.

Hardness:

6 - Orthoclase

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Niocalite

Gladstone-Dale:

CI meas= 0.011 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.002 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2171,KPDmeas= 0.2152,KC= 0.2175
Ncalc = 1.72

Optical Data:

Biaxial (-), a=1.7-1.701, b=1.714-1.721, g=1.72-1.73, bire=0.0200-0.0290, 2V(Calc)=64-66, 2V(Meas)=34-56.

Calculated Properties of Niocalite

Electron Density:

Bulk Density (Electron Density)=3.24 gm/cc
note: Specific Gravity of Niocalite =3.29 gm/cc.

Fermion Index:

Fermion Index = 0.0074096198
Boson Index = 0.9925903802

Photoelectric:

PE_Niocalite= 22.25 barns/electron
U=PE_Niocalite x rElectron Density= 72.01 barns/cc.

Radioactivity:

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

Niocalite Classification

Dana Class:

56.02.04.06 (56)Sorosilicate Si2O7 Groups and O, OH, F. and H2O

(56.02)with cations in [4] and/or >[4] coordination

(56.02.04)Cuspidine - Wohlerite group

56.02.04.01 Baghdadite Ca3(Zr,Ti)Si2O9 P 2₁/a 2/m

56.02.04.02 Burpalite Na2CaZrSi2O7F2 P 2₁/a 2/m

56.02.04.03 Cuspidine Ca4Si2O7(F,OH)2 P 2₁/c 2/m

56.02.04.04 Lavenite (Na,Ca)2(Mn,Fe)(Zr,Ti,Nb)Si2O7(O,OH,F) P 2₁/a 2/m

56.02.04.05 Wohlerite NaCa2(Zr,Nb)Si2O7(O,OH,F)2 P 2₁/m 2/m

56.02.04.06 Niocalite Ca14Nb2(Si2O7)4O6F2 Pa m

56.02.04.07 Hiortdahlite (Ca,Na,Y)3(Zr,Ti)Si2O7(F,O,OH)2 P1 1

56.02.04.08 Rosenbuschite (Ca,Na)3(Zr,Ti)Si2O8F P1 1

56.02.04.09 Hainite Na4Ca8(Ti,Zr,Mn,Fe)3Si8O28F8 P1 1

56.02.04.10 Janhaugite (Na,Ca)3(Mn,Fe)3(Ti,Zr,Nb)2Si4O15(OH,F,O)3 P 2₁/n 2/m

56.02.04.11 Jennite Ca9Si6O18(OH)6•8H2O P1 1

56.02.04.12 Komarovite (Ca,Mn)2(Nb,Ti)2Si2O7(O,F)2•3.5(H2O) Unk Ortho

56.02.04.13 Natrokomarovite* Na6CaNb6[Si4O12F2•4(H2O) C mmm 2/m 2/m 2/m

56.02.04.14 Suolunite Ca2Si2O5(OH)2•(H2O) F dd2 mm2

56.02.04.15 Mongolite Ca4Nb6Si5O24(OH)10•5(H2O) Unk Tetra

56.02.04.16 Kristiansenite! Ca2ScSn(Si2O7)(Si2O6OH) C1 1

56.02.04.17 Kochite! Na2(Na,Ca)4Ca4(Mn,Ca)2Zr2Ti2(Si2O7)4(O,F)4F4 P1 1

56.02.04.18 Marianoite! Na2Ca4(Nb,Zr)2(Si2O7)2(O,F)4 P 2₁ 2/m

Strunz Class:

09.BE.17 09 - SILICATES (Germanates)

09.B - Sorosilicates

09.BE -Si2O7 groups with additional anions;

09.BE.17 Baghdadite Ca3(Zr,Ti)Si2O9 P 2₁/a 2/m

09.BE.17 Janhaugite (Na,Ca)3(Mn,Fe)3(Ti,Zr,Nb)2Si4O15(OH,F,O)3 P 2₁/n 2/m

09.BE.17 Burpalite Na2CaZrSi2O7F2 P 2₁/a 2/m

09.BE.17 Cuspidine Ca4Si2O7(F,OH)2 P 2₁/c 2/m

09.BE.17 Hiortdahlite (Ca,Na,Y)3(Zr,Ti)Si2O7(F,O,OH)2 P1 1

09.BE.17 Lavenite (Na,Ca)2(Mn,Fe)(Zr,Ti,Nb)Si2O7(O,OH,F) P 2₁/a 2/m

09.BE.17 Niocalite Ca14Nb2(Si2O7)4O6F2 Pa m

09.BE.17 Normandite! NaCa(Mn,Fe)(Ti,Nb,Zr)Si2O7(O,F)2 P 2₁/a 2/m

09.BE.17 Wohlerite NaCa2(Zr,Nb)Si2O7(O,OH,F)2 P 2₁/m 2/m

09.BE.17 Marianoite! Na2Ca4(Nb,Zr)2(Si2O7)2(O,F)4 P 2₁ 2/m

Other Niocalite Information

References:

NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Niocalite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

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

Niocalite

Ca14Nb2(Si2O7)4O6F2
Dana No: 56.02.04.06 Strunz No: 09.BE.17
Locality:

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