Chestermanite Mineral Data

General Chestermanite Information

Chemical Formula:

Mg2(Fe+++,Mg,Al,Sb+++++)BO3O2

Composition:

Molecular Weight = 192.66 gm

Magnesium 27.75 % Mg 46.02 % MgO

Aluminum 1.40 % Al 2.65 % Al₂O₃

Iron 17.39 % Fe 24.87 % Fe₂O₃

Boron 5.61 % B 18.07 % B₂O₃

Antimony 6.32 % Sb 8.40 % Sb₂O₅

Oxygen 41.52 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg₂Fe³⁺_0.6Mg_0.2Al_0.1Sb_0.1BO₅

IMA Status:

Approved IMA 1988

Locality:

Twin Lakes region, Fresno County, California, USA. Link to MinDat.org Location Data.

Name Origin:

Named for Charles W. Chesterman (1913-1991), U. S. Geologist who discovered the mineral.

Synonym:

ICSD 71036

PDF 45-1415

Chestermanite Image

Images:

Chestermanite Ludwigite

Comments: Black capillary crystals of ludwigite with green inclusions of chestermanite in impure marble.
Location: Near Potter Pass, Fresno County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Chestermanite Crystallography

Axial Ratios:

a:b:c =1.5095:1:0.2462

Cell Dimensions:

a = 18.525, b = 12.272, c = 3.0218, Z = 8; V = 686.97 Den(Calc)= 3.73

Crystal System:

Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pbam

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

By Intensity(I/I_o): 5.114(1), 2.559(0.91), 2.169(0.57),

Physical Properties of Chestermanite

Cleavage:

None

Color:

Gray green, Black, Black green.

Density:

3.72

Diaphaneity:

Transparent

Habit:

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

Hardness:

6 - Orthoclase

Luster:

Vitreous - Silky

Streak:

light gray green

Optical Properties of Chestermanite

Gladstone-Dale:

CI meas= 0.092 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.094 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2062,KPDmeas= 0.2067,KC= 0.2275
Ncalc = 1.85

Optical Data:

Biaxial (+), a=1.753, b=1.763, g=1.791, bire=0.0380, 2V(Calc)=64, 2V(Meas)=63.

Pleochroism (x):

dark blue green.

Pleochroism (y):

green.

Pleochroism (z):

pale yellow brown.

Calculated Properties of Chestermanite

Electron Density:

Bulk Density (Electron Density)=3.61 gm/cc
note: Specific Gravity of Chestermanite =3.72 gm/cc.

Fermion Index:

Fermion Index = 0.04
Boson Index = 0.96

Photoelectric:

PE_{Chestermanite}= 25.12 barns/electron
U=PE_{Chestermanite} x rElectron Density= 90.60 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Chestermanite is Not Radioactive

Chestermanite Classification

Dana Class:

24.02.01.05 (24)Borates - Anhydrous

(24.02)where (A)2 BO2 [XO3]

(24.02.01)Ludwigite Group (Space Group: Pbam)

24.02.01.01 Ludwigite Mg2FeBO5 Pbam 2/m 2/m 2/m

24.02.01.02 Vonsenite Fe2FeBO5 Pbam 2/m 2/m 2/m

24.02.01.03 Azoproite (Mg,Fe)2(Fe,Ti,Mg)BO5 Pbam 2/m 2/m 2/m

24.02.01.04 Bonaccordite Ni2FeBO5 Pbam 2/m 2/m 2/m

24.02.01.05 Chestermanite Mg2(Fe,Mg,Al,Sb)BO3O2 Pbam 2/m 2/m 2/m

24.02.01.06 Fredrikssonite Mg2(Mn,Fe)O2(BO3) Pbam 2/m 2/m 2/m

Strunz Class:

06.AB.40 06 - BORATES

06.A - Monoborates

06.AB -BO3, with additional anions; 1(D) + OH, etc.

06.AB.40 Blatterite (Mn,Mg)35Sb3(Mn,Fe)9(BO3)16O32 Pnnm 2/m 2/m 2/m

06.AB.40 Chestermanite Mg2(Fe,Mg,Al,Sb)BO3O2 Pbam 2/m 2/m 2/m

06.AB.40 Orthopinakiolite (Mg,Mn)2MnBO5 Pnnm 2/m 2/m 2/m

06.AB.40 Takeuchiite Mg2MnO2(BO3) Pnnm 2/m 2/m 2/m

Other Chestermanite Information

References:

NAME( Dana8) PHYS. PROP.(Am.Min.,Vol.75,p431,1990) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Chestermanite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - WWW-MINCRYST

Search for Chestermanite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Chestermanite :

Ask about Chestermanite 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 Espa�ol

Print or Cut-and-Paste your Chestermanite Specimen Label here :

Chestermanite

Mg2(Fe+++,Mg,Al,Sb+++++)BO3O2
Dana No: 24.02.01.05 Strunz No: 06.AB.40
Locality:

Notes:

Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.