Milarite Mineral Data

Milarite Mineral Data +

General Milarite Information

Chemical Formula:

K2Ca4Al2Be4Si24O60·(H2O)

Composition:

Molecular Weight = 1,980.55 gm

Potassium 3.95 % K 4.76 % K₂O

Calcium 8.09 % Ca 11.33 % CaO

Beryllium 1.82 % Be 5.05 % BeO

Aluminum 2.72 % Al 5.15 % Al₂O₃

Silicon 34.03 % Si 72.81 % SiO₂

Hydrogen 0.10 % H 0.91 % H₂O

Oxygen 49.28 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

K₂Ca₄Al₂Be₄(Si₂₄O₆₀)·(H₂O)

Environment:

Granitic pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1870

Locality:

Val Milar, Switzerland. Link to MinDat.org Location Data.

Name Origin:

Named after its locality.

Synonym:

ICSD 6260

PDF 35-459

Milarite Image

Images:

Milarite

Comments: Single transparent crystal of yellow Milarite.
Location: Near Rossing, Namibia. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Images:

Milarite

Comments: Blocky, barrel-shaped crystal of milarite on muscovite..
Location: Jagauaracu, Minas Gerais, Brazil. Scale: Crystal size 2.5 x 1 x 1 cm.
© Rob Lavinsky

Milarite Crystallography

Axial Ratios:

a:c = 1:1.32997

Cell Dimensions:

a = 10.41, c = 13.845, Z = 1; V = 1,299.35 Den(Calc)= 2.53

Crystal System:

Hexagonal - Dihexagonal DipyramidalH-M Symbol (6/m 2/m 2/m) Space Group: P 6/mcc

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

By Intensity(I/I_o): 3.307(1), 2.88(0.9), 4.16(0.65),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Hawthorne F C , Kimata M , Cerny P , Ball N A , Rossman G R , Grice J D , American Mineralogist , 76 (1991) p.1836-1856, The crystal chemistry of the milarite-group minerals, sample #25 from Guanajuato, Note: U(1,2) of WatB/NaB changed to match symmetry constraints

View Additional jPOWD Structure files for Milarite
[1] [10] [2] [3] [4] [5] [6] [7] [8] [9]

Physical Properties of Milarite

Cleavage:

[0001] Imperfect, [1120] Imperfect

Color:

Colorless, White, Greenish white, Yellowish white.

Density:

2.52

Diaphaniety:

Transparent to translucent

Fracture:

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

Habit:

Crystalline - Coarse - Occurs as well-formed coarse sized crystals.

Habit:

Granular - Generally occurs as anhedral to subhedral crystals in matrix.

Habit:

Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).

Hardness:

6 - Orthoclase

Luminescence:

Fluorescent.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Milarite

Dichroism (e):

colorless.

Dichroism (w):

colorless.

Gladstone-Dale:

CI meas= -0.013 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.009 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2124,KPDmeas= 0.2132,KC= 0.2104

Optical Data:

Uniaxial (-), e=1.529-1.548, w=1.532-1.551, bire=0.0030-0.0160.

Calculated Properties of Milarite

Electron Density:

r_electron=2.52 gm/cc
note: r_Milarite=2.53 gm/cc.

Fermion Index

Fermion Index = 0.03444
Boson Index = 0.96556

Photoelectric:

PE_Milarite= 2.79 barns/electron
U=PE_Milarite x r_electron= 7.04 barns/cc.

Radioactivity:

GRapi = 56.71 (Gamma Ray American Petroleum Institute Units)

Estimated Radioactivity from Milarite - barely detectable

Milarite Classification

Dana Class:

63.2.1a.12 (63)Cyclosilicate Condensed Rings

(63.2)Milarite - Osumilite type (6x2) Double Rings

(63.2.1a)Milarite - Osumilite group (Milarite - Osumilite subgroup)

63.2.1a.1 Brannockite KSn2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.2 Chayesite K(Mg,Fe)4Fe(Si12O30) P 6/mcc 6/m 2/m 2/m

63.2.1a.3 Darapiosite KNa2Zr[Li(Mn,Zr)2Si12O30] P 6/mcc 6/m 2/m 2/m

63.2.1a.4 Eifelite KNa3Mg4Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.5 Merrihueite (K,Na)2(Fe,Mg)5Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.6 Osumilite-(Fe) (K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.7 Osumilite-(Mg) (K,Na)(Mg,Fe)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.8 Poudretteite KNa2B3Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.9 Sugilite KNa2(Fe,Mn,Al)2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.10 Yagiite (Na,K)3Mg4(Al,Mg)6(Si,Al)24O60 P 6/mmc 6/m 2/m 2/m

63.2.1a.11 Dusmatovite K(K,Na,[])(Mn,Y,Zr)2(Zn,Li)3Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.12 Milarite K2Ca4Al2Be4Si24O60·(H2O) P 6/mcc 6/m 2/m 2/m

63.2.1a.13 Sogdianite (K,Na)2(Li,Fe,Al)3ZrSi12O30 P 6/mmm 6/m 2/m 2/m

63.2.1a.14 Roedderite (Na,K)2(Mg,Fe)5Si12O30 P 6₃/mmc 6/m 2/m 2/m

63.2.1a.15 Berezanskite! KLi3Ti2Si12O30 P 6/mcc 6/m 2/m 2/m

63.2.1a.16 Shibkovite! K(Ca,Mn,Na)2(K2-x,[]x)2ZnSi12O30(x~0.8) P 6/mcc 6/m 2/m 2/m

63.2.1a.17 Trattnerite! (Fe,Mg)2(Mg,Fe)3(Si12O30) P 6/mcc 6/m 2/m 2/m

63.2.1a.18 Almarudite! K([],Na)2(Mn,Fe,Mg)2(Be,Al)3[Si12O30] P 6/mcc 6/m 2/m 2/m

63.2.1a.19 IMA2003-045a! (Sc,Ca)2KBe3Si12O30 P 6/mmc 6/m 2/m 2/m

Strunz Class:

VIII/E.22-20 VIII - Silicates

VIII/E - Cyklosilicates, double six rings [Si12O30]12-

VIII/E.22 - Millarite - Osumilite series

VIII/E.22-10 Poudretteite KNa2B3Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-20 Milarite K2Ca4Al2Be4Si24O60·(H2O) P 6/mcc 6/m 2/m 2/m

VIII/E.22-22 Almarudite! K([],Na)2(Mn,Fe,Mg)2(Be,Al)3[Si12O30] P 6/mcc 6/m 2/m 2/m

VIII/E.22-25 Trattnerite! (Fe,Mg)2(Mg,Fe)3(Si12O30) P 6/mcc 6/m 2/m 2/m

VIII/E.22-30 Eifelite KNa3Mg4Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-40 Roedderite (Na,K)2(Mg,Fe)5Si12O30 P 6₃/mmc 6/m 2/m 2/m

VIII/E.22-50 Chayesite K(Mg,Fe)4Fe(Si12O30) P 6/mcc 6/m 2/m 2/m

VIII/E.22-60 Merrihueite (K,Na)2(Fe,Mg)5Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-70 Yagiite (Na,K)3Mg4(Al,Mg)6(Si,Al)24O60 P 6/mmc 6/m 2/m 2/m

VIII/E.22-80 Osumilite-(Mg) (K,Na)(Mg,Fe)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-90 Osumilite-(Fe) (K,Na)(Fe,Mg)2(Al,Fe)3(Si,Al)12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-100 Emeleusite Na4Li2Fe2Si12O30 Pnna 2/m 2/m 2/m

VIII/E.22-110 Sugilite KNa2(Fe,Mn,Al)2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-120 Sogdianite (K,Na)2(Li,Fe,Al)3ZrSi12O30 P 6/mmm 6/m 2/m 2/m

VIII/E.22-125 Berezanskite! KLi3Ti2Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-130 Darapiosite KNa2Zr[Li(Mn,Zr)2Si12O30] P 6/mcc 6/m 2/m 2/m

VIII/E.22-133 Shibkovite! K(Ca,Mn,Na)2(K2-x,[]x)2ZnSi12O30(x~0.8) P 6/mcc 6/m 2/m 2/m

VIII/E.22-135 Dusmatovite K(K,Na,[])(Mn,Y,Zr)2(Zn,Li)3Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-140 Brannockite KSn2Li3Si12O30 P 6/mcc 6/m 2/m 2/m

VIII/E.22-150 Armenite BaCa2Al6Si9O30·2(H2O) Pnc2 mm2

Other Milarite Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

Search for Milarite using:

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

Visit our Advertisers for Milarite :
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 Milarite Mineral Data :

Ask about Milarite 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 Milarite Specimen Label here :

Milarite

K2Ca4Al2Be4Si24O60·(H2O)
Dana No: 63.2.1a.12 Strunz No: VIII/E.22-20
Locality:

Notes: