Wightmanite Mineral Data

Wightmanite Mineral Data +

[Newest Minerals] [Minerals for Sale] [Educational Articles] [About Us] [Image Gallery]
John Betts - Fine Minerals
Classic minerals, out-of-print books & magazines, plus informative articles for collectors

General Wightmanite Information

Chemical Formula:

Mg5(BO3)O(OH)5·2(H2O)

Composition:

Molecular Weight = 317.40 gm

Magnesium 38.29 % Mg 63.49 % MgO

Boron 3.41 % B 10.97 % B₂O₃

Hydrogen 2.86 % H 25.54 % H₂O

Oxygen 55.45 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg₅(BO₃)O(OH)₅·2(H₂O)

Environment:

Metamorphosed limestone.

IMA Status:

Approved IMA 1962

Locality:

Crestmore Quarry, 5 miles NW of Riverside, Riverside Co., California. Link to MinDat.org Location Data.

Synonym:

ICSD 34371

PDF 14-640

Wightmanite Image

Images:

Wightmanite

Comments: Tan silky prismatic wightmanite in pale blue calcite.
Location: Crestmore Quarry, Riverside County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Wightmanite Crystallography

Axial Ratios:

a:b:c =4.3391:1:5.8575

Cell Dimensions:

a = 13.46, b = 3.102, c = 18.17, Z = 4; beta = 91.6° V = 758.35 Den(Calc)= 2.78

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: I2/m

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

By Intensity(I/I_o): 9.07(1), 10.7(1), 3.03(0.3),

Physical Properties of Wightmanite

Cleavage:

[010] Perfect, [100] Distinct

Color:

Colorless, Light green.

Density:

2.6

Diaphaniety:

Transparent

Hardness:

5.5 - Knife Blade

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Wightmanite

Gladstone-Dale:

CI meas= 0.032 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.095 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2149,KPDmeas= 0.2297,KC= 0.2374

Optical Data:

Biaxial (-), a=1.585, b=1.603, g=1.604, bire=0.0190, 2V(Calc)=26, 2V(Meas)=33.

Calculated Properties of Wightmanite

Electron Density:

r_electron=2.65 gm/cc
note: r_Wightmanite=2.60 gm/cc.

Fermion Index

Fermion Index = 0.04533
Boson Index = 0.95467

Photoelectric:

PE_Wightmanite= 0.96 barns/electron
U=PE_Wightmanite x r_electron= 2.54 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Wightmanite is Not Radioactive

Wightmanite Classification

Dana Class:

26.1.2.1 (26)Hydrated Borates Containing Hydroxyl or Halogen

(26.1)Dana Type

(26.1.2)Dana Group

26.1.2.1 Wightmanite Mg5(BO3)O(OH)5·2(H2O) I2/m 2/m

Strunz Class:

V/G.06-20 V - Nitrates, Carbonates and Borates

V/G - "Insel" borates [BO3]3- "inseln"

V/G.06 - Berborite - Qilianshanite series

V/G.06-10 Berborite Be2(BO3)(OH,F)·(H2O) P 6₃ 6

V/G.06-20 Wightmanite Mg5(BO3)O(OH)5·2(H2O) I2/m 2/m

V/G.06-30 Shabynite Mg5(BO3)Cl2(OH)5·4(H2O) Unk. Mono

V/G.06-40 Canavesite Mg2(CO3)(HBO3)·5(H2O) P 2/m 2/m

V/G.06-50 Sakhaite Ca3Mg(BO3)2(CO3)·0.36(H2O) F 4₁32 4 3 2

V/G.06-60 Qilianshanite NaH4(CO3)(BO3)·2(H2O) C 2 2

Other Wightmanite Information

References:

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

See Also:

Links to other databases for Wightmanite :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas 12 -École des Mines de Paris

Search for Wightmanite using:

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

Visit our Advertisers for Wightmanite :
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 Wightmanite Mineral Data :

Ask about Wightmanite 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 Wightmanite Specimen Label here :

Wightmanite

Mg5(BO3)O(OH)5·2(H2O)
Dana No: 26.1.2.1 Strunz No: V/G.06-20
Locality:

Notes: