Bobierrite Mineral Data

General Bobierrite Information

Chemical Formula:

Mg3(PO4)2•8(H2O)

Composition:

Molecular Weight = 406.98 gm

Magnesium 17.92 % Mg 29.71 % MgO

Phosphorus 15.22 % P 34.88 % P₂O₅

Hydrogen 3.96 % H 35.41 % H₂O

Oxygen 62.90 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg₃(PO₄)₂•8(H₂O)

Environment:

Formed from the chemical alteration of guano deposits (Mejillones, Chile; Imperial Canyon lava tubes, Kenya), and an elephant tusk (Edgerton, Minnesota, USA).

IMA Status:

Valid Species (Pre-IMA) 1868

Locality:

Found on Mejillones Island, Chile. In Western Australia, found in the Pilbara district, at Wodgina. From Marlborough, New Zealand. In the USA, sound near Edgerton, Pipestone Co., Minne Link to MinDat.org Location Data.

Name Origin:

In honor of Pierre Adolphe Bobierre (1823-1881), French agricultural chemist, who first described the mineral.

Name Pronunciation:

Bobierrite + Pronunciation

Bobierrite Image

Images:

Bobierrite

Comments: Crystal group of bobierrite partially covered by yellow calcite.
Location: Zheleznyi Mine, Kovdor, Kola Penisula, Russia. Scale: Crystal size 1 cm.
© John Veevaert

Images:

Strontiowhitlockite Bobierrite

Comments: Pale white to pink fine grained strontiowhitlockite with bobierrite.
Location: Kovdor Massif, Kola Peninsula, Murmansk District, Russia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Bobierrite Crystallography

Axial Ratios:

a:b:c =0.1671:1:0.3604

Cell Dimensions:

a = 4.667, b = 27.926, c = 10.067, Z = 4; beta = 105.01° V = 1,267.27 Den(Calc)= 2.13

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/c

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

By Intensity(I/I_o): 6.96(1), 2.94(0.27), 8.04(0.18),

Physical Properties of Bobierrite

Cleavage:

{010} Perfect

Color:

Colorless, Gray, White.

Density:

2.195

Diaphaneity:

Transparent

Hardness:

2-2.5 - Gypsum-Finger Nail

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Bobierrite

Gladstone-Dale:

CI meas= -0.014 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.045 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2547,KPDmeas= 0.2472,KC= 0.2436
Ncalc = 1.52 - 1.53

Optical Data:

Biaxial (+), a=1.51-1.5468, b=1.52-1.5533, g=1.543-1.582, bire=0.0330-0.0352, 2V(Calc)=52-68, 2V(Meas)=53-71.

Calculated Properties of Bobierrite

Electron Density:

Bulk Density (Electron Density)=2.27 gm/cc
note: Specific Gravity of Bobierrite =2.20 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_Bobierrite= 1.21 barns/electron
U=PE_Bobierrite x rElectron Density= 2.75 barns/cc.

Radioactivity:

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

Bobierrite Classification

Dana Class:

40.03.07.01 (40)Hydrated Phosphates, etc

(40.03)where (A++)3 (XO4)2 � x(H2O)

(40.03.07)Dana Group

40.03.07.01 Bobierrite Mg3(PO4)2•8(H2O) C 2/c 2/m

40.03.07.02 Manganohornesite (Mn,Mg)3(AsO4)2•8(H2O) P 2₁/c 2/m

Strunz Class:

08.CE.35 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CE -With only medium-sized cations, RO4:H2O � 1:2.5

08.CE.35 Bobierrite Mg3(PO4)2•8(H2O) C 2/c 2/m

Other Bobierrite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Bobierrite :
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

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

Bobierrite

Mg3(PO4)2•8(H2O)
Dana No: 40.03.07.01 Strunz No: 08.CE.35
Locality:

Notes:

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