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 % P2 O5
Hydrogen 3.96 % H 35.41 % H2 O
Oxygen 62.90 % O
______ ______
100.00 % 100.00 % = TOTAL OXIDE
Empirical Formula:
Mg3 (PO4 )2 •8(H2 O)
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:
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
X Ray Diffraction:
By Intensity(I/Io ): 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:
PEBobierrite = 1.21 barns/electronU=PEBobierrite x r Electron 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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Bobierrite
Mg3(PO4)2•8(H2O)
Dana No: 40.03.07.01 Strunz No: 08.CE.35
Locality:
Notes:
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