Motukoreaite Mineral Data

Motukoreaite Mineral Data +

General Motukoreaite Information

Chemical Formula:

Na2Mg38Al24(CO3)13(SO4)8(OH)108·56(H2O)

Composition:

Molecular Weight = 6,011.40 gm

Sodium 0.76 % Na 1.03 % Na₂O

Magnesium 15.36 % Mg 25.48 % MgO

Aluminum 10.77 % Al 20.35 % Al₂O₃

Hydrogen 3.69 % H 32.97 % H₂O

Carbon 2.60 % C 9.52 % CO₂

Sulfur 4.27 % S 10.65 % SO₃

Oxygen 62.55 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Na₂Mg₃₈Al₂₄(CO₃)₁₃(SO₄)₈(OH)₁₀₈·56(H₂O)

Environment:

Rim cement in volcanic breccias in weathered submarine environments.

IMA Status:

Approved IMA 1977

Locality:

Brown's Island, (Motukorea) within Waitemata Harbor, New Zealand. Link to MinDat.org Location Data.

Name Origin:

Named for the Maori name for the locality (Motukorea - "island of the cormorants.").

Synonym:

ICSD 29523

PDF 41-1380

Motukoreaite Image

Images:

Motukoreaite

Comments: Colorless, tabular crystals of motukoreaite.
Location: Stradnerkogel Quarry, Wilhelmsdorf, Styria, Austria. Scale: Picture size 1.5 mm.
© Thomas Witzke / Abraxas-Verlag

Motukoreaite Crystallography

Axial Ratios:

a:c = 1:3.65351

Cell Dimensions:

a = 9.172, c = 33.51, Z = 0.4; V = 2,441.37 Den(Calc)= 1.64

Crystal System:

Trigonal - Hexagonal ScalenohedralH-M Symbol (3 2/m) Space Group: R 3m

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

By Intensity(I/I_o): 11.32(1), 3.72(0.7), 5.58(0.6),4.59(0.6), 2.58(0.4), 1.924(0.3), 2.39(0.3),

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

Rius J , Plana F , Neues Jahrbuch fur Mineralogie, Monatshefte , 1986 (1986) p.263-272, Contribution to the superstructure resolution of the double layer, mineral motukoreaite, Locality: the Emile Baudot bank, western Mediterranean

Physical Properties of Motukoreaite

Cleavage:

[???] Perfect

Color:

Yellow green, White, Light yellow.

Density:

1.48 - 1.53, Average = 1.5

Habit:

Fibrous - Crystals made up of fibers.

Habit:

Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)

Hardness:

1-1.5 - Talc or a little harder

Streak:

white

Optical Properties of Motukoreaite

Gladstone-Dale:

CI meas= -0.377 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.264 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.311,KPDmeas= 0.3389,KC= 0.2461

Optical Data:

Uniaxial (?), a=1.51, b=1.51, bire=0.0000.

Calculated Properties of Motukoreaite

Electron Density:

r_electron=1.69 gm/cc
note: r_Motukoreaite=1.64 gm/cc.

Fermion Index

Fermion Index = 0.01627
Boson Index = 0.98373

Photoelectric:

PE_Motukoreaite= 1.05 barns/electron
U=PE_Motukoreaite x r_electron= 1.77 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Motukoreaite is Not Radioactive

Motukoreaite Classification

Dana Class:

17.1.7.1 (17)Compound Carbonates

(17.1)with miscellaneous formulae

(17.1.7)Dana Group

17.1.7.1 Motukoreaite Na2Mg38Al24(CO3)13(SO4)8(OH)108·56(H2O) R 3m 3 2/m

Strunz Class:

VI/D.14-20 VI - Sulfates,Chromates,Molybdates and Tungstates

VI/D - Water-bearing sulfates with unfamiliar anions. cations of medium and very big size

VI/D.14 - Metavoltine - Slavikite series

VI/D.14-10 Metavoltine K4Na4(Fe,Zn)Fe6(SO4)12O2·20(H2O) P 3 3

VI/D.14-20 Motukoreaite Na2Mg38Al24(CO3)13(SO4)8(OH)108·56(H2O) R 3m 3 2/m

VI/D.14-22 Nikischerite! NaFe6Al3(SO4)2(OH)18(H2O)12 R 3 3

VI/D.14-23 Shigaite Mn7Al4(SO4)2(OH)22·8(H2O) R 3 3

VI/D.14-25 Wermlandite (Ca,Mg)Mg7(Al,Fe)2(SO4)2(OH)18·12(H2O) P 3c1 3 2/m

VI/D.14-30 Lannonite HCa4Mg2Al4(SO4)8F9·32(H2O) Unk Tetra

VI/D.14-40 Slavikite NaMg2Fe5(SO4)7(OH)6·33(H2O) R 3 3

Other Motukoreaite Information

References:

NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

Search for Motukoreaite using:

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

Visit our Advertisers for Motukoreaite :
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 Motukoreaite Mineral Data :

Ask about Motukoreaite 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 Motukoreaite Specimen Label here :

Motukoreaite

Na2Mg38Al24(CO3)13(SO4)8(OH)108·56(H2O)
Dana No: 17.1.7.1 Strunz No: VI/D.14-20
Locality:

Notes: