Roselite-beta Mineral Data

General Roselite-beta Information

Chemical Formula:

Ca2(Co,Mg)(AsO4)2•2(H2O)

Composition:

Molecular Weight = 444.30 gm

Calcium 18.04 % Ca 25.24 % CaO

Magnesium 1.37 % Mg 2.27 % MgO

Cobalt 9.95 % Co 12.65 % CoO

Arsenic 33.73 % As 51.73 % As₂O₅

Hydrogen 0.91 % H 8.11 % H₂O

Oxygen 36.01 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Ca₂Co_0.75Mg_0.25(AsO₄)₂•2(H₂O)

Environment:

Secondary arsenate mineral.

IMA Status:

Valid Species (Pre-IMA) 1955

Locality:

Schneeberg, Saxony, Germany. Link to MinDat.org Location Data.

Name Origin:

Named for its dimorphic relationship with roselite.

Name Pronunciation:

Roselite-beta

Synonym:

Beta-roselite

Roselite-beta Image

Images:

Roselite-beta

Comments: Clear, rose-colored roselite-beta crystalline grains.
Location: Bou Azzer, Anti-Atlas Mountains, Morocco. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Images:

Roselite-beta

Comments: Deep red, well crystallized roselite-beta covering a small pocket in white calcite.
Location: Ahrbar, Bou-Azzer area. Scale: 7 x 4 x 4.5 cm.
© Fabre Minerals

Roselite-beta Crystallography

Axial Ratios:

a:b:c =0.7659:1:0.723

Cell Dimensions:

a = 5.89, b = 7.69, c = 5.56, Z = 1; alpha = 112.6°, beta = 70.8°, gamma = 119.4° V = 191.29 Den(Calc)= 3.86

Crystal System:

Triclinic Space Group: P 1 or P1

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

By Intensity(I/I_o): 2.78(1), 1.714(0.8), 3.2(0.8),3.07(0.8), 3.56(0.6), 2.16(0.4), 3.33(0.4), 5.07(0.3),

Physical Properties of Roselite-beta

Cleavage:

{010} Perfect

Color:

Dark rose red.

Density:

3.71

Diaphaneity:

Transparent to Translucent

Habit:

Granular - Generally occurs as anhedral to subhedral crystals in matrix.

Hardness:

3.5-4 - Copper Penny-Fluorite

Luster:

Vitreous (Glassy)

Streak:

pale red

Optical Properties of Roselite-beta

Gladstone-Dale:

CI meas= -0.039 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.042 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1996,KPDmeas= 0.1991,KC= 0.1916
Ncalc = 1.71

Optical Data:

Biaxial (-), a=1.723, b=1.737, g=1.756, bire=0.0330

Calculated Properties of Roselite-beta

Electron Density:

Bulk Density (Electron Density)=3.56 gm/cc
note: Specific Gravity of Roselite-beta =3.71 gm/cc.

Fermion Index:

Fermion Index = 0.0017853601
Boson Index = 0.9982146399

Photoelectric:

PE_{Roselite-beta}= 28.49 barns/electron
U=PE_{Roselite-beta} x rElectron Density= 101.47 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Roselite-beta is Not Radioactive

Roselite-beta Classification

Dana Class:

40.02.02.07 (40)Hydrated Phosphates, etc

(40.02)where A++ (B++)2 (XO4) ï¿½ x(H2O)

(40.02.02)Fairfieldite Subgroup (Triclinic: P-1ï¿½)

40.02.02.01 Fairfieldite Ca2(Mn,Fe)(PO4)2•2(H2O) P1 1

40.02.02.02 Messelite Ca2(Fe,Mn)(PO4)2•2(H2O) P1 1

40.02.02.03 Collinsite Ca2(Mg,Fe)(PO4)2•2(H2O) P1 1

40.02.02.04 Cassidyite Ca2(Ni,Mg)(PO4)2•2(H2O) P1 1

40.02.02.05 Talmessite Ca2Mg(AsO4)2•2(H2O) P1 1

40.02.02.06 Gaitite Ca2Zn(AsO4)2•2(H2O) P1 1

40.02.02.07 Roselite-beta Ca2(Co,Mg)(AsO4)2•2(H2O) P 1 or P1 Tri

40.02.02.08 Parabrandtite Ca2Mn(AsO4)•2(H2O) P1,P 1 Tri

40.02.02.09 Hillite! Ca2(Zn,Mg)[PO4]2•2(H2O) P1 1

40.02.02.10 Nickeltalmessite! Ca2Ni(AsO4)2•2H2O P 1

Strunz Class:

08.CG.10 08 - PHOSPHATES, ARSENATES, VANADATES

08.C - Phosphates without Additional Anions, with H2O

08.CG -With large and medium-sized cations, RO4:H2O = 1:1

08.CG.10 Brandtite Ca2(Mn,Mg)(AsO4)2•2(H2O) P 2₁/c 2/m

08.CG.10 Roselite Ca2(Co,Mg)(AsO4)2•2(H2O) P 2₁/c 2/m

08.CG.10 Roselite-beta Ca2(Co,Mg)(AsO4)2•2(H2O) P 1 or P1 Tri

08.CG.10 Zincroselite Ca2Zn(AsO4)2•2(H2O) P 2₁/c 2/m

08.CG.10 Wendwilsonite Ca2(Mg,Co)(AsO4)2•2(H2O) P 2₁/c 2/m

Other Roselite-beta Information

References:

NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Roselite-beta :
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 - MinDAT
9 - Mineralienatlas (Deutsch)
10 - Online Mineral Museum
11 - QUT Mineral Atlas
12 - Ruff.Info

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Print or Cut-and-Paste your Roselite-beta Specimen Label here :

Roselite-beta

Ca2(Co,Mg)(AsO4)2•2(H2O)
Dana No: 40.02.02.07 Strunz No: 08.CG.10
Locality:

Notes:

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