Searlesite Mineral Data

Searlesite Mineral Data +

[Express Minerals] [Minerals for Sale] [About Us] [En EspaÃƒï¿½Ã‚Â±ol] [Mineral Gallery]
Fabre Minerals - Europe's first Internet mineral dealer, on the web since 1996

General Searlesite Information

Chemical Formula:

NaBSi2O5(OH)2

Composition:

Molecular Weight = 203.98 gm

Sodium 11.27 % Na 15.19 % Na₂O

Silicon 27.54 % Si 58.91 % SiO₂

Boron 5.30 % B 17.06 % B₂O₃

Hydrogen 0.99 % H 8.83 % H₂O

Oxygen 54.90 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

NaBSi₂O₅(OH)₂

Environment:

Continental alkaline evaporite deposits and alcalic-pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1914

Locality:

Searles Lake, San Bernardino Co., California. Link to MinDat.org Location Data.

Name Origin:

Named after it's locality.

Synonym:

ICSD 12134

PDF Jun-37

Searlesite Image

Images:

Searlesite

Comments: Clear, prismatic crystal of Searlesite.
Location: Point of Rocks Mesa. Colfax County, New Mexico, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Searlesite Crystallography

Axial Ratios:

a:b:c =1.1304:1:0.6948

Cell Dimensions:

a = 7.972, b = 7.052, c = 4.9, Z = 2; beta = 93.95° V = 274.82 Den(Calc)= 2.46

Crystal System:

Monoclinic - SphenoidalH-M Symbol (2) Space Group: P 2₁

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

By Intensity(I/I_o): 8.01(1), 4.06(0.5), 3.48(0.4),

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

Ghose S , Wan C , American Mineralogist , 61 (1976) p.123-129, Structural chemistry of borosilicates, part II: Searlesite, NaBSi2O5(OH):, Absolute configuration, hydrogen locations, and refinement of the structure, Note: unable to reproduce any of the reported bond lengths

Physical Properties of Searlesite

Cleavage:

[100] Perfect, [010] Distinct, [001] Distinct

Color:

White, Light brown.

Density:

2.45

Diaphaniety:

Transparent to translucent

Habit:

Fibrous - Crystals made up of fibers.

Habit:

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

Habit:

Spherical - Spherical, rounded aggregates.

Hardness:

1-2 - Between Talc and Gypsum

Luminescence:

Non-fluorescent.

Luster:

Vitreous (Glassy)

Magnetism:

Nonmagnetic

Streak:

white

Optical Properties of Searlesite

Gladstone-Dale:

CI meas= 0.01 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.014 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.215,KPDmeas= 0.2159,KC= 0.2181

Optical Data:

Biaxial (-), a=1.515-1.524, b=1.531-1.533, g=1.535, bire=0.0110-0.0200

Calculated Properties of Searlesite

Electron Density:

r_electron=2.45 gm/cc
note: r_Searlesite=2.45 gm/cc.

Fermion Index

Fermion Index = 0.02367
Boson Index = 0.97633

Photoelectric:

PE_Searlesite= 1.32 barns/electron
U=PE_Searlesite x r_electron= 3.23 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Searlesite is Not Radioactive

Searlesite Classification

Dana Class:

74.3.5.4 (74)Phyllosilicate Modulated Layers

(74.3)with joined strips

(74.3.5)Na phyllosilicates

74.3.5.1 Natrosilite Na2Si2O5 P 2₁/a 2/m

74.3.5.2 Makatite Na2Si4O8(OH)2·4(H2O) P 2₁/c 2/m

74.3.5.3 Silinaite NaLiSi2O5·2(H2O) A2/n 2/m

74.3.5.4 Searlesite NaBSi2O5(OH)2 P 2₁ 2

Strunz Class:

VIII/G.05-10 VIII - Silicates

VIII/G - Intermediate between chain- and layered silicates

VIII/G.05 - Silinaite - Makatite series

VIII/G.05-05 Silinaite NaLiSi2O5·2(H2O) A2/n 2/m

VIII/G.05-10 Searlesite NaBSi2O5(OH)2 P 2₁ 2

VIII/G.05-20 Makatite Na2Si4O8(OH)2·4(H2O) P 2₁/c 2/m

Other Searlesite Information

References:

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

Search for Searlesite using:

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

Visit our Advertisers for Searlesite :

AA Mineral Specimens

B & L Fine Minerals

Crystal Vaults

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

MineralsWeb Fine Minerals

Rockshop.cz

T G Fine Minerals

Wrights Rock Shop

Translate Searlesite Mineral Data :

Ask about Searlesite 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 Searlesite Specimen Label here :

Searlesite

NaBSi2O5(OH)2
Dana No: 74.3.5.4 Strunz No: VIII/G.05-10
Locality:

Notes: