Bearsite Mineral Data

General Bearsite Information

Chemical Formula:

Be2(AsO4)(OH)•4(H2O)

Composition:

Molecular Weight = 246.01 gm

Beryllium 7.33 % Be 20.33 % BeO

Arsenic 30.45 % As 46.71 % As₂O₅

Hydrogen 3.69 % H 32.95 % H₂O

Oxygen 58.53 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Be₂(AsO₄)(OH)•4(H₂O)

Environment:

Oxidation zone of a polymetallic deposit.

IMA Status:

Approved IMA 1962

Locality:

Kazakhstan. Link to MinDat.org Location Data.

Name Origin:

Named for the composition (Be, Arsenic).

Name Pronunciation:

Bearsite

Synonym:

ICSD 74041

PDF 45-378

Bearsite Crystallography

Axial Ratios:

a:b:c =0.2317:1:0.1932

Cell Dimensions:

a = 8.55, b = 36.9, c = 7.13, Z = 12; beta = 97.816° V = 2,228.58 Den(Calc)= 2.20

Crystal System:

Monoclinic Space Group: Cc or C 2/c

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

By Intensity(I/I_o): 6.95(1), 3.31(0.8), 4.23(0.6),

Physical Properties of Bearsite

Color:

White.

Density:

1.8 - 2, Average = 1.9

Diaphaneity:

Translucent

Habit:

Encrustations - Forms crust-like aggregates on matrix.

Habit:

Fibrous - Crystals made up of fibers.

Habit:

Striated - Parallel lines on crystal surface or cleavage face.

Streak:

white

Optical Properties of Bearsite

Gladstone-Dale:

CI meas= -0.108 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= 0.043 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2264,KPDmeas= 0.2621,KC= 0.2365
Ncalc = 1.43 - 1.52

Optical Data:

Biaxial (-), a=1.49, b=1.502, g=1.502, bire=0.0120

Calculated Properties of Bearsite

Electron Density:

Bulk Density (Electron Density)=2.18 gm/cc
note: Specific Gravity of Bearsite =2.20 gm/cc.

Fermion Index:

Fermion Index = 0.07
Boson Index = 0.93

Photoelectric:

PE_Bearsite= 20.07 barns/electron
U=PE_Bearsite x rElectron Density= 43.79 barns/cc.

Radioactivity:

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

Bearsite Classification

Dana Class:

42.06.01.02 (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen

(42.06)where (AB)2 (XO4) Zq ï¿½ x(H2O)

(42.06.01)Moraesite Group

42.06.01.01 Moraesite Be2(PO4)(OH)•4(H2O) Cc,C 2/c Mono

42.06.01.02 Bearsite Be2(AsO4)(OH)•4(H2O) Cc or C 2/c Mono

Strunz Class:

08.DA.05 08 - PHOSPHATES, ARSENATES, VANADATES

08.D - Phosphates, etc

08.DA -With small (and occasionally larger) cations

08.DA.05 Bearsite Be2(AsO4)(OH)•4(H2O) Cc or C 2/c Mono

08.DA.05 Moraesite Be2(PO4)(OH)•4(H2O) Cc,C 2/c Mono

Other Bearsite Information

References:

NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Bearsite :
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

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

Bearsite

Be2(AsO4)(OH)•4(H2O)
Dana No: 42.06.01.02 Strunz No: 08.DA.05
Locality:

Notes:

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