Jennite Mineral Data

Jennite Mineral Data +

General Jennite Information

Chemical Formula:

Ca9Si6O18(OH)6·8H2O

Composition:

Molecular Weight = 1,063.37 gm

Calcium 33.92 % Ca 47.46 % CaO

Silicon 15.85 % Si 33.90 % SiO₂

Hydrogen 2.09 % H 18.64 % H₂O

Oxygen 48.15 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ca₉Si₆O₁₈(OH)₆·8(H₂O)

Environment:

Late stage mineral in metamorphosed limestone.

IMA Status:

Approved IMA 1966

Locality:

Crestmore Quarry, 5 miles NW of Riverside, Riverside Co. California. Link to MinDat.org Location Data.

Name Origin:

Named for Clarence Marvin Jenni (1896-1973), American mineral collector and director of the Geological Museum, University of Missouri.

Jennite Image

Images:

Jennite

Comments: Bright white fibrous jennite veinlet in rock.
Location: Crestmore Quarry, Riverside County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Jennite Crystallography

Axial Ratios:

a:b:c =1.4557:1:1.5046

Cell Dimensions:

a = 10.576, b = 7.265, c = 10.931, Z = 1; alpha = 101.3°, beta = 96.98°, gamma = 109.65° V = 769.89 Den(Calc)= 2.29

Crystal System:

Triclinic - PinacoidalH-M Symbol ( 1) Space Group: P1

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

By Intensity(I/I_o): 10.5(1), 2.92(0.8), 3.04(0.6),

Physical Properties of Jennite

Cleavage:

[001] Distinct

Color:

White.

Density:

2.32 - 2.33, Average = 2.32

Habit:

Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).

Habit:

Platy - Sheet forms (e.g. micas).

Hardness:

3.5 - Copper Penny

Luminescence:

Sometimes Fluorescent, Short UV=weak white.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Jennite

Gladstone-Dale:

CI meas= -0.033 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= -0.049 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2451,KPDmeas= 0.2414,KC= 0.2335

Optical Data:

Biaxial (-), a=1.548-1.552, b=1.562-1.564, g=1.57-1.571, bire=0.0190-0.0220, 2V(Calc)=72-74, 2V(Meas)=74.

Calculated Properties of Jennite

Electron Density:

r_electron=2.37 gm/cc
note: r_Jennite=2.33 gm/cc.

Fermion Index

Fermion Index = 0.00809
Boson Index = 0.99191

Photoelectric:

PE_Jennite= 4.74 barns/electron
U=PE_Jennite x r_electron= 11.23 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Jennite is Not Radioactive

Jennite Classification

Dana Class:

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

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

(56.2.4)Cuspidine - Wohlerite group

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

56.2.4.2 Burpalite Na2CaZrSi2O7F2 P 2₁/a 2/m

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

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

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

56.2.4.6 Niocalite Ca14Nb2(Si2O7)4O6F2 Pa m

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

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

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

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

56.2.4.11 Jennite Ca9Si6O18(OH)6·8H2O P1 1

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

56.2.4.13 Na-komarovite? Na6CaNb6[Si4O12F2·4(H2O) C mmm 2/m 2/m 2/m

56.2.4.14 Suolunite Ca2Si2O5(OH)2·(H2O) F dd2 mm2

56.2.4.15 Mongolite Ca4Nb6Si5O24(OH)10·5(H2O) Unk Tetra

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

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

Strunz Class:

VIII/D.18-10 VIII - Silicates

VIII/D - Unclassified silicates, mostly cations of big size Na, K, Ca, Sr, Pb

VIII/D.18 - Jennite series

VIII/D.18-10 Jennite Ca9Si6O18(OH)6·8H2O P1 1

Other Jennite Information

References:

NAME( Dana8) PHYS. PROP.(Dana8, AmMin 90:772) OPTIC PROP.(Dana8)

Search for Jennite using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Jennite :
AA Mineral Specimens
A-Rocks Auction
Adams Minerals
B and L Minerals
Dakota Matrix
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Minernet.it
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Jennite Mineral Data :

Ask about Jennite 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 Jennite Specimen Label here :

Jennite

Ca9Si6O18(OH)6·8H2O
Dana No: 56.2.4.11 Strunz No: VIII/D.18-10
Locality:

Notes: