Cavansite Mineral Data

General Cavansite Information

Chemical Formula:

Ca(VO)Si4O10•4(H2O)

Composition:

Molecular Weight = 451.42 gm

Calcium 8.88 % Ca 12.42 % CaO

Vanadium 11.28 % V 20.15 % V₂O₅

Silicon 24.89 % Si 53.24 % SiO₂

Hydrogen 1.79 % H 15.96 % H₂O

Oxygen 53.16 % O

______ ______

100.00 % 101.77 % = TOTAL OXIDE

Empirical Formula:

CaV⁵⁺Si₄O₁₁•4(H₂O)

Environment:

Secondary mineralization in basalts and andesites.

IMA Status:

Approved IMA 1973

Locality:

Deccan trap basalts, Poona, India. Link to MinDat.org Location Data.

Name Origin:

Named after its composition of calcium, vanadium, and silicon.

Name Pronunciation:

Cavansite + Pronunciation

Synonym:

ICSD 1906

PDF 25-182

Cavansite Image

Images:

Cavansite

Comments: Brilliant blue balls of acicular crystals of cavansite to 1 cm in size richly scattered about a matrix of colorless stilbite crystals.
Location: Wagholi, Poona district, Maharashtra, India. Scale: 7.5 x 9 x 8 cm.
© Dan Weinrich

Cavansite Crystallography

Axial Ratios:

a:b:c =0.7148:1:0.7019

Cell Dimensions:

a = 9.778, b = 13.678, c = 9.601, Z = 4; V = 1,284.07 Den(Calc)= 2.33

Crystal System:

Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pcmn

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

By Intensity(I/I_o): 7.964(1), 6.854(0.5), 6.132(0.25),

Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize
Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu
Help on Above

Forms: ( 1 0 1) ( 1 1 0)

Warning: this java applet does not work in some browsers because of security restrictions.

Physical Properties of Cavansite

Cleavage:

{010} Good

Color:

Greenish blue, Dark blue.

Density:

2.21 - 2.31, Average = 2.25

Diaphaneity:

Subtransparent

Fracture:

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

Hardness:

3-4 - Calcite-Fluorite

Luster:

Vitreous (Glassy)

Streak:

bluish white

Optical Properties of Cavansite

Gladstone-Dale:

CI meas= 0.07 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= 0.098 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2342,KPDmeas= 0.2414,KC= 0.2596
Ncalc = 1.57 - 1.6

Optical Data:

Biaxial (+), a=1.542, b=1.544, g=1.551, bire=0.0090, 2V(Calc)=58, 2V(Meas)=52.

Calculated Properties of Cavansite

Electron Density:

Bulk Density (Electron Density)=2.27 gm/cc
note: Specific Gravity of Cavansite =2.26 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_Cavansite= 4.15 barns/electron
U=PE_Cavansite x rElectron Density= 9.42 barns/cc.

Radioactivity:

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

Cavansite Classification

Dana Class:

74.03.07.01 (74)Phyllosilicate Modulated Layers

(74.03)with joined strips

(74.03.07)V phyllosilicates

74.03.07.01 Cavansite Ca(VO)Si4O10•4(H2O) Pcmn 2/m 2/m 2/m

74.03.07.02 Pentagonite Ca(VO)Si4O10•4(H2O) Ccm21 mm2

Strunz Class:

09.EA.50 09 - SILICATES (Germanates)

09.E - Phyllosilicates

09.EA -Single nets of tetrahedra with 4-, 5-, (6-), and 8-membered rings

09.EA.50 Cavansite Ca(VO)Si4O10•4(H2O) Pcmn 2/m 2/m 2/m

Other Cavansite Information

References:

NAME( MinRec) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Cavansite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - CalTech Mineral Spectroscopy
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 - HyperPhysics
13 - MinDAT
14 - Mineralienatlas (Deutsch)
15 - Online Mineral Museum
16 - QUT Mineral Atlas
17 - Ruff.Info
18 - WWW-MINCRYST

Search for Cavansite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Cavansite :

Ask about Cavansite 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 Cavansite Specimen Label here :

Cavansite

Ca(VO)Si4O10•4(H2O)
Dana No: 74.03.07.01 Strunz No: 09.EA.50
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.