Brewsterite-Sr Mineral Data

General Brewsterite-Sr Information

Chemical Formula:

(Sr,Ba)Al4Si12O32•10(H2O)

Composition:

Molecular Weight = 1,330.04 gm

Potassium 0.06 % K 0.07 % K₂O

Barium 4.96 % Ba 5.53 % BaO

Strontium 9.35 % Sr 11.06 % SrO

Aluminum 8.36 % Al 15.79 % Al₂O₃

Silicon 25.23 % Si 53.98 % SiO₂

Hydrogen 1.52 % H 13.54 % H₂O

Oxygen 50.52 % O

______ ______

100.00 % 99.99 % = TOTAL OXIDE

Empirical Formula:

Sr_1.42Ba_0.48K_0.02Al_4.12Si_11.95O₃₂•10(H₂O)

Environment:

A hydrothermal mineral occurring in vugs of massive volcanic rocks and in veins. Renamed by the zeolite commission to brewsterite-Sr.

IMA Status:

Valid Species (Pre-IMA) 1822

Locality:

Strontian at Argyleshite, Scotland. Link to MinDat.org Location Data.

Name Origin:

Named after David Brewster (1781-1868), Scottish physicist, who studied the optical properties of minerals and the element Strontium.

Name Pronunciation:

Brewsterite-Sr + Pronunciation

Synonym:

Brewsterite

Strontiumbrewsterite

Brewsterite-Sr Image

Images:

Brewsterite-Sr

Comments: Translucent brewsterite crystals on matrix.
Location: Yellow Lake, Olalla, Osoyoos Mining Division, British Columbia, Canada. Scale: 35x30x20 mm.
© John Betts - Fine Minerals

Brewsterite-Sr Crystallography

Axial Ratios:

a:b:c =0.3865:1:0.4415

Cell Dimensions:

a = 6.793, b = 17.573, c = 7.759, Z = 1; beta = 94.54° V = 923.31 Den(Calc)= 2.39

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/m

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

By Intensity(I/I_o): 4.66(1), 2.922(0.8), 3.268(0.4),

Physical Properties of Brewsterite-Sr

Cleavage:

{010} Perfect

Color:

White, Yellowish white, Gray..

Density:

2.45

Diaphaneity:

Transparent to translucent

Habit:

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

Hardness:

5 - Apatite

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Brewsterite-Sr

Gladstone-Dale:

CI meas= 0.019 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= -0.006 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2155,KPDmeas= 0.2102,KC= 0.2143
Ncalc = 1.51 - 1.53

Optical Data:

Biaxial (+), a=1.51, b=1.512, g=1.523, bire=0.0130

Calculated Properties of Brewsterite-Sr

Electron Density:

Bulk Density (Electron Density)=2.37 gm/cc
note: Specific Gravity of Brewsterite-Sr =2.39 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_{Brewsterite-Sr}= 31.34 barns/electron
U=PE_{Brewsterite-Sr} x r_electron= 74.12 barns/cc.

Radioactivity:

GRapi = 0.85 (Gamma Ray American Petroleum Institute Units)
Concentration of Brewsterite-Sr per GRapi unit =117.90 (%)

Estimated Radioactivity from Brewsterite-Sr - barely detectable

Brewsterite-Sr Classification

Dana Class:

77.01.07.01 (77)Tectosilicate Zeolite group

(77.01)true zeolites

(77.01.07)Brewsterite and related species

77.01.07.01 Brewsterite-Sr (Sr,Ba)Al4Si12O32•10(H2O) P 2₁/m 2/m

77.01.07.01a Brewsterite-Ba! (Ba,Sr)Al2Si6O16•5(H2O) P 2₁/m,P 2₁ Mono

77.01.07.02 Yugawaralite CaAl2Si6O16•4(H2O) Pc m

77.01.07.03 Goosecreekite CaAl2Si6O16•5(H2O) P 2₁ 2

77.01.07.04 Roggianite Ca2[Be(OH)2Al2Si4O13]•<2•5(H2O) I 4/mcm 4/m 2/m 2/m

Strunz Class:

09.GE.20 09 - SILICATES (Germanates)

09.G - Tektosilicates with Zeolitic H2O

09.GE -Chains of T10O20 Tetrahedra

09.GE.20 Brewsterite-Ba! (Ba,Sr)Al2Si6O16•5(H2O) P 2₁/m,P 2₁ Mono

09.GE.20 Brewsterite-Sr (Sr,Ba)Al4Si12O32•10(H2O) P 2₁/m 2/m

Other Brewsterite-Sr Information

References:

NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Ford32)

See Also:

Links to other databases for Brewsterite-Sr :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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Print or Cut-and-Paste your Brewsterite-Sr Specimen Label here :

Brewsterite-Sr

(Sr,Ba)Al4Si12O32•10(H2O)
Dana No: 77.01.07.01 Strunz No: 09.GE.20
Locality:

Notes:

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