Bigcreekite Mineral Data

Bigcreekite Mineral Data

[What's New] [Mineral Galleries] [Sale Items] [About Us] [Contacts]
At AA Mineral Specimens, we source quality Mineral Specimens, Fossils, Gemstones,
Decorative Stones, Lapidary Material and Specimen Sets world-wide

General Bigcreekite Information

Chemical Formula:

BaSi2O5·4(H2O)

Composition:

Molecular Weight = 345.56 gm

Barium 39.74 % Ba 44.37 % BaO

Silicon 16.26 % Si 34.78 % SiO₂

Hydrogen 2.33 % H 20.85 % H₂O

Oxygen 41.67 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

BaSi₂O₅·4(H₂O)

Environment:

Found in fractures in a sanborite-quartz gneiss. Double-chain silicate; structure.

IMA Status:

Approved IMA 1999 (Dana # Added)

Locality:

Esquire no. 7 claim, along Big Creek, Fresno County, California, USA. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Synonym:

IMA1999-015

Bigcreekite Image

Images:

Bigcreekite Gillespite Sanbornite

Comments: Tiny white, spherical patterns, halo-like crystals of bigcreekite to about 0.5mm and reddish gillespite in a matrix of pale yellowish sanbornite.
Location: Trumbull Peak, Mariposa Co., California, United States. Scale: 2.5 x 2 x 2cm.
© Tom Loomis / Dakota Matrix

Bigcreekite Crystallography

Axial Ratios:

a:b:c =0.5582:1:2.0302

Cell Dimensions:

a = 5.038, b = 9.024, c = 18.321, Z = 4; V = 832.93 Den(Calc)= 2.76

Crystal System:

Orthorhombic - DipyramidalH-M Symbol (2/m 2/m 2/m) Space Group: P nma

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

By Intensity(I/I_o): 5.068(1)(013), 4.054(0.85)(022), 2.257(0.75)(126),2.706(0.6)(124), 2.974(0.45)(031), 2.327(0.4)(035), 9.19(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

Basciano L C , Groat L A , Roberts A C , Gault R A , Dunning G E , Walstrom R E , The Canadian Mineralogist , 39 (2001) p.761-768, Bigcreekite: A new barium silicate mineral species from Fresno County, California, Locality: Fresno County, California, USA

Physical Properties of Bigcreekite

Cleavage:

[001] Perfect, [010] Perfect

Color:

Colorless, White.

Density:

2.66

Diaphaniety:

Transparent

Fracture:

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

Habit:

Subhedral Crystals - Occurs as crystals which tend to exhibit a recognizable crystal shape.

Habit:

Tabular - Form dimensions are thin in one direction.

Hardness:

2-3 - Gypsum-Calcite

Luster:

Vitreous - Pearly

Streak:

white

Optical Properties of Bigcreekite

Gladstone-Dale:

CI meas= -0.012 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.024 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1952,KPDmeas= 0.2025,KC= 0.2

Optical Data:

Biaxial (+), a=1.537, b=1.538, g=1.541, bire=0.0040, 2V(Calc)=62, 2V(Meas)=59.2. Dispersion r < v moderate.

Calculated Properties of Bigcreekite

Electron Density:

r_electron=2.52 gm/cc
note: r_Bigcreekite=2.66 gm/cc.

Fermion Index

Fermion Index = 0.07862
Boson Index = 0.92138

Photoelectric:

PE_Bigcreekite= 168.55 barns/electron
U=PE_Bigcreekite x r_electron= 425.58 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Bigcreekite is Not Radioactive

Bigcreekite Classification

Dana Class:

66.2.1.2 (66)Inosilicate Double-Width Unbranched Chains, W=2

(66.2)with P=2 non-amphibole configuration

(66.2.1)Dana Group

66.2.1.1 Plancheite Cu8Si8O22(OH)4·(H2O) Pcnb 2/m 2/m 2/m

66.2.1.2 Bigcreekite ! BaSi2O5·4(H2O) P nma 2/m 2/m 2/m

Strunz Class:

VIII/H.02-60 VIII - Silicates

VIII/H - Phyllosilicates (layered), Tetragonal or pseudotetragonal layered structures [Si4O10]4- and others

VIII/H.02 - Davanite - Dalyite series

VIII/H.02-10 Cuprorivaite CaCuSi4O10 P 4/nnc 4/m 2/m 2/m

VIII/H.02-20 Wesselsite! SrCuSi4O10 P 4/ncc 4/m 2/m 2/m

VIII/H.02-30 Effenbergerite BaCuSi4O10 P 4/nnc 4/m 2/m 2/m

VIII/H.02-40 Gillespite BaFeSi4O10 P 4/ncc 4/m 2/m 2/m

VIII/H.02-50 Sanbornite BaSi2O5 Pmnb 2/m 2/m 2/m

VIII/H.02-60 Bigcreekite BaSi2O5·4(H2O) P nma 2/m 2/m 2/m

Other Bigcreekite Information

References:

NAME( AmMin, Vol 87, p 355) PHYS. PROP.(AmMin, Vol 87, p 355) OPTIC PROP.(AmMin, Vol 87, p 355)

See Also:

Links to other databases for Bigcreekite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 -Google Images 4 -Google Scholar 5 -MinDAT 6 -MinMax(Deutsch) 7 -MinMax(English) 8 -Mineralienatlas (Deutsch) 9 -QUT Mineral Atlas

Search for Bigcreekite using:

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

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

Translate Bigcreekite Mineral Data :

Ask about Bigcreekite 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 Bigcreekite Specimen Label here :

Bigcreekite

BaSi2O5·4(H2O)
Dana No: 66.2.1.2 Strunz No: VIII/H.02-60
Locality:

Notes: